Archive for the ‘Crispr’ Category

(more about Power Words)

cancerAny of more than 100 different diseases, each characterized by the rapid, uncontrolled growth of abnormal cells. The development and growth of cancers, also known as malignancies, can lead to tumors, pain and death.

Cas9An enzyme that geneticists are now using to help edit genes.It can cut through DNA, allowing it to fix broken genes, splice in new ones or disable certain genes. Cas9 is shepherded to the place it is supposed to make cuts by CRISPRs, a type of genetic guides. The Cas9 enzyme came from bacteria. When viruses invade a bacterium, this enzyme can chop up the germs DNA, making it harmless.

cellThe smallest structural and functional unit of an organism. Typically too small to see with the unaided eye, it consists of a watery fluid surrounded by a membrane or wall. asyeasts, molds, bacteria and some algae, are composed of only one cell.

clinicaltrialA research trial that involves people.

CRISPRAn abbreviation pronounced crisper for the term clustered regularly interspaced short palindromic repeats. These are pieces of RNA, an information-carrying molecule. They are copied from the genetic material of viruses that infect bacteria. When a bacterium encounters a virus that it was previously exposed to, it produces an RNA copy of the CRISPR that contains that virus genetic information. The RNA then guides an enzyme, called Cas9, to cut up the virus and make it harmless. Scientists are now building their own versions of CRISPR RNAs. These lab-made RNAs guide the enzyme to cut specific genes in other organisms. Scientists use them, like a genetic scissors, to edit or alter specific genes so that they can then study how the gene works, repair damage to broken genes, insert new genes or disable harmful ones.

disorder(in medicine) A condition where the body does not work appropriately, leading to what might be viewed as an illness. This term can sometimes be used interchangeably with disease.

DNA(short for deoxyribonucleic acid) Along, double-stranded and spiral-shaped molecule inside most living cells that carries genetic instructions. It is built on a backbone of phosphorus, oxygen, and carbon atoms. In all living things, from plants and animals to microbes, these instructions tell cells which molecules to make.

engineerA person who uses science to solve problems. As a verb, to engineer means to design a device, material or process that will solve some problem or unmet need.

gene(adj. genetic) A segment of DNA that codes, or holds instructions, for a cells production of a protein. Offspring inherit genes from their parents. Genes influence how an organism looks and behaves.

geneticHaving to do with chromosomes, DNA and the genes contained within DNA. The field of science dealing with these biological instructions is known as genetics. People who work in this field are geneticists.

hemoglobinA molecule that binds to oxygen in the blood, carrying it around to tissues.

immune(adj.) Having to do with the immunity. (v.) Able to ward off a particular infection.Alternatively, this term can be used to mean an organism shows no impacts from exposure to a particular poison or process. More generally, the term may signal that something cannot be hurt by a particular drug, disease or chemical.

insightThe ability to gain an accurate and deep understanding of a situation just by thinking about it, instead of working out a solution through experimentation.

multiplemyelomaThis cancer starts in a type of white blood cells known as plasma cells. Part of the immune system, they help guard the body from germs and other harmful substances.

muscleA type of tissue used to produce movement by contracting its cells, known as muscle fibers. Muscle is rich in protein, which is why predatory species seek prey containinglots of this tissue.

mutation(v. mutate) Some change that occurs to a gene in an organisms DNA. Some mutations occur naturally. Others can be triggered by outside factors, such as pollution, radiation, medicines or something in the diet. A gene with this change is referred to as a mutant.

nerveA long, delicate fiberthat transmits signalsacross the body of an animal. An animals backbone contains many nerves, some of which control the movement of its legs or fins, and some of which convey sensations such as hot, cold or pain.

neuronAn impulse-conducting cell. Such cells are found in the brain, spinal column and nervous system.

oxygenA gas that makes up about 21 percent of Earth's atmosphere. All animals and many microorganisms need oxygen to fuel their growth (and metabolism).

pharmaceuticalsMedicines, especially prescription drugs.

plasma (in medicine) The colorless fluid part of blood.

proteinA compoundmade from one or more long chains of amino acids. Proteins are an essential part of all living organisms. They form the basis of living cells, muscle and tissues; they also do the work inside of cells. Among the better-known, stand-alone proteins are thehemoglobin (in blood) and the antibodies (also in blood) that attempt to fight infections. Medicines frequently work by latching onto proteins.

redblood cellColored red by hemoglobin, these cells move oxygen from the lungs to all tissues of the body. Red blood cells are too small to be seen by the unaided eye.

retinaA layer at the back of the eyeball containing cells that are sensitive to light and that trigger nerve impulses that travel along the optic nerve to the brain, where a visual image is formed.

RNAA molecule that helps read the genetic information contained in DNA. A cells molecular machinery reads DNA to create RNA, and then reads RNA to create proteins.

sarcomaA family of more than 70 cancers that begin in bones or in connective tissues.

technologyThe application of scientific knowledge for practical purposes, especially in industry or the devices, processes and systems that result from those efforts.

therapy(adj. therapeutic) Treatment intended to relieve or heal a disorder.

variantA version of something that may come in different forms. (ingenetics) A gene having a slight mutation that may have left its host species somewhat better adapted for its environment.

wombAnother name for the uterus, the organ in mammals in which a fetus grows and matures in preparation for birth.

Original post:
Genetics CRISPR enters its first human trials - Science News for Students

In a recent review, scientists highlight the potential of gene editing technologies like CRISPR/Cas9 to not only understand the molecular mechanisms behind Parkinsons disease, but also identify new targets for treatment.

The review study, Interrogating Parkinsons disease associated redox targets: Potential application of CRISPR editing, was published in the journal Free Radical Biology and Medicine.

One of the hallmarks of PD is the loss of dopamine-producing neurons in the substantia nigra a brain region involved in the control of voluntary movements, and one of the most affected in PD. This occurs due to the clustering of a protein called alpha-synuclein in structures commonly known as Lewy bodies inside neurons.

Parkinsons is complex and multifactorial disease, with both genetic and environmental factors playing a role in either triggering or exacerbating the disease.

Genetic causes can explain 10% of all cases of PD called familial PD , meaning that in the majority of the cases (sporadic PD) there is an interplay between genetics and environmental risk factors.

Researchers atSechenov Universityin Russia and theUniversity of Pittsburgh reviewed the role of metabolic pathways, especially problems with mitochondria cells powerhouses and iron accumulation, as well as mechanisms in cell death (called apoptosis and ferroptosis) in the development and progression of Parkinsons disease.

These processes were discussed in the context of genome editing technologies, namely CRISPR/Cas9 a technique that allows scientists to edit genomes, inserting or deleting DNA sequences, with precision, efficiency and flexibility.

CRISPR is a promising technology, a strategy to find new effective treatments to neurodegenerative diseases, Margarita Artyukhova, a student at the Institute for Regenerative Medicineat Sechenov and the study first author, said in a press release.

Mitochondria dont work as they should in people withPD, resulting in shortages of cellular energy that cause neurons to fail and ultimately die, particularlydopamine-producing neurons. Faulty mitochondria are also linked to the abnormal production of reactive oxygen species, leading to oxidative stressan imbalance between the production of free radicals and the ability of cells to detoxify them that also damages cells over time.

Because mitochondrial dysfunction is harmful, damaged mitochondria are usually eliminated (literally, consumed and expelled) in a process called mitophagy an important cleansing process in which two genes, called PINK1 and PRKN, play crucialroles. Harmful changes in mitophagy regulation is linked with neurodegeneration in Parkinsons.

Previous studies with animal models carrying mutations in the PINK1and PRKNgenes showed that these animals developed typical features of PD mitochondrial dysfunction, muscle degeneration, and a marked loss of dopamine-producing neurons.

PINK1codes for an enzyme that protects brain cells against oxidative stress, whilePRKNcodes for a protein called parkin. Both are essential for proper mitochondrial function and recycling by mitophagy. Mutations in both the PINK1 and PRKNgene have been linked with early-onset PD.

However, new research suggests that the role of PINK1 and PRKNin Parkinsons could be more complex and involve other genes likePARK7(DJ-1), SNCA (alpha-synuclein) andFBXO7 as well as a fat molecule called cardiolipin.

CRISPR/Cas9 genome editing technology may be used to help assess the role of different genetic players in Parkinsons disease, and to look for unknown genes associated with disease progression and development. Moreover, this technology can help generate animal and cellular models that might help scientists decipher the role of certain proteins in Parkinsons and discover potential new treatment targets.

Iron is another important metabolic cue in Parkinsons. While its essential for normal physiological functions, excessive levels of iron can be toxic and lead to the death of dopamine-producing neurons in the substantia nigra.

Iron may also interact with dopamine, promoting the production of toxic molecules that damage mitochondria and cause alpha-synuclein buildup within neurons.

CRISPR/Cas9 technology can be used to help dissect the role of proteins involved in iron transport inside neurons, which in turn may aid in designing therapies to restore iron levels to normal in the context of Parkinsons disease.

Finally, researchers summarized evidence related to the role of two cell death pathways ferroptosis and apoptosis in PD. Ferroptosis is an iron-dependent cell death mechanism by which iron changes fat (lipid) molecules, turning them toxic to neurons. This process has been implicated in cell death associated with degenerative diseases like Parkinsons, and drugs that work to inhibit ferroptosis have shown an ability to halt neurodegeneration in animal models of the disease.

Apoptosis refers to a programmed cell death mechanism, as opposed to cell death caused by injury. Both apoptosis and ferroptosis speed the death of dopaminergic neurons.

CRISPR/Cas9 may help to pinpoint the key players in cell death that promote the loss of dopaminergic neurons in Parkinsons disease, while understanding the array of proteins that are involved in these processes.

These insights into the mechanisms of PD pathology [disease mechanisms] may be used for the identification of new targets for therapeutic interventions and innovative approaches to genome editing, including CRISPR/Cas9, the researchers wrote.

Genome editing technology is currently being used in clinical trials to treat patients with late-stage cancers and inherited blood disorders, Artyukhova notes in the release.

These studies allow us to see vast potential of genome editing as a therapeutic strategy. Its hard not to be thrilled and excited when you understand that progress of genome editing technologies can completely change our understanding of treatment of Parkinsons disease and other neurodegenerative disorders, she adds.

Patricia holds a Ph.D. in Cell Biology from University Nova de Lisboa, and has served as an author on several research projects and fellowships, as well as major grant applications for European Agencies. She has also served as a PhD student research assistant at the Department of Microbiology & Immunology, Columbia University, New York.

Read the original here:
CRISPR/Cas9 Potential in Advancing Parkinson's Understanding and Treatment Focus of Review Study - Parkinson's News Today

We are pleased to announce Technology Networks Explores the CRISPR Revolution. Through a series of exclusive interviews with world-renowned scientists and bioethicists, Technology Networks Explores the CRISPR Revolution will investigate the ground-breaking research taking place in the CRISPR space, CRISPR "controversies" and whether the CRISPR technology looks set to fulfil its promise of revolutionizing science.

The series will feature interviews with researchers behind the discovery of the CRISPR mechanism, such as Professor Francisco Mojica, the scientist involved its development as a gene-editing tool, Professor Jennifer Doudna, and the "godfather" of human genome research, Professor George Church.

The series will also explore the latest technologies available in the CRISPR "toolbox" including industry perspectives, its application in agriculture and farming through a conversation with Professor Alison Van Eenennaam and insights into the global conversation surrounding its ethical implications from Professor Glenn Cohen.

Kicking off the series on Oct 14th is an interview with the humble and immensely influential microbiologist, Professor Francisco Mojica.

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Technology Networks Explores the CRISPR Revolution Coming Soon - Technology Networks

Duchenne muscular dystrophy (DMD) is a rare but devastating genetic disorder that causes muscle loss and physical impairments. Researchers at the University of Missouri School of Medicine have shown in a mouse study that the powerful gene editing technique known as CRISPR may provide the means for lifelong correction of the genetic mutation responsible for the disorder.

Children with DMD have a gene mutation that interrupts the production of a protein known as dystrophin. Without dystrophin, muscle cells become weaker and eventually die. Many children lose the ability to walk, and muscles essential for breathing and heart function ultimately stop working.

"Research has shown that CRISPR can be used to edit out the mutation that causes the early death of muscle cells in an animal model," said Dongsheng Duan, PhD, Margaret Proctor Mulligan Professor in Medical Research in the Department of Molecular Microbiology and Immunology at the MU School of Medicine and the senior author of the study. "However, there is a major concern of relapse because these gene-edited muscle cells wear out over time. If we can correct the mutation in muscle stem cells, then cells regenerated from the edited stem cells will no longer carry the mutation. A one-time treatment of the muscle stem cells with CRISPR could result in continuous dystrophin expression in regenerated muscle cells."

In collaboration with other MU colleagues and researchers from the National Center for Advancing Translational Sciences, Johns Hopkins School of Medicine and Duke University, Duan explored whether muscle stem cells from mice could be efficiently edited. The researchers first delivered the gene editing tools to normal mouse muscle through AAV9, a virus that was recently approved by the U.S. Food and Drug Administration to treat spinal muscular atrophy.

"We transplanted AAV9 treated muscle into an immune-deficient mouse," said Michael Nance, a MD-PhD program student in Duan's lab and the lead author of the paper. "The transplanted muscle died first then regenerated from its stem cells. If the stem cells were successfully edited, the regenerated muscle cells should also carry the edited gene."

The researchers' reasoning was correct, as they found abundant edited cells in the regenerated muscle. They then tested if muscle stem cells in a mouse model of DMD could be edited with CRISPR. Similar to what they found in normal muscle, the stem cells in the diseased muscle were also edited. Cells regenerated from these edited cells successfully produced dystrophin.

"This finding suggests that CRISPR gene editing may provide a method for lifelong correction of the genetic mutation in DMD and potentially other muscle diseases," Duan said. "Our research shows that CRISPR can be used to effectively edit the stem cells responsible for muscle regeneration. The ability to treat the stem cells that are responsible for maintaining muscle growth may pave the way for a one-time treatment that can provide a source of gene-edited cells throughout a patient's life."

With more study, the researchers hope this stem cell-targeted CRISPR approach may one day lead to long-lasting therapies for children with DMD.

Reference: Nance et al. 2019.AAV9 Edits Muscle Stem Cells in Normal and Dystrophic Adult Mice. Molecular Therapy.DOI: https://doi.org/10.1016/j.ymthe.2019.06.012.

This article has been republished from the following materials. Note: material may have been edited for length and content. For further information, please contact the cited source.

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Researchers Use CRISPR to Correct Mutation in Duchenne Muscular Dystrophy Model - Technology Networks

A team has used a lentiviral capsid-based bionanoparticle system to deliver CRISPR-Cas9 gene editing therapies, reducing undesired effects.

Researchers have developed an improved CRISPR delivery system for gene editing, through a lentiviral capsid system. The team say that their findings could be useful in research and clinical applications by improving safety and avoiding possible immune responses.

using a traditional lentiviral vector allows the bionanoparticle to efficiently and safely deliver CRISPR-Cas9

The team, from Wake Forest Institute of Regenerative Medicine (WFIRM), US, packaged the Cas9 protein and guide RNA together within a lentiviral capsid-based bionanoparticle system.

Previously, the two components had to be delivered separately which was not as convenient, said Dr Baisong Lu, assistant professor of regenerative medicine at WFIRM and one of the lead authors of the paper.

Conventional CRISPR-Cas9 is not completely accurate and could potentially cut unexpected locations, causing unwanted results.

However, the using a traditional lentiviral vector allows the bionanoparticle to efficiently and safely deliver CRISPR-Cas9. The researchers observed that it reduced off-target rates compared to regular CRISPR-Cas9.

A similar strategy should be translatable to other editor proteins for gene disruption, said Anthony Atala, MD, director of WFIRM and a co-author of the paper. We may be able to utilise this to package and deliver other RNPs into mammalian cells, which has been difficult to achieve so far.

The findings were published in Nucleic Acids Research.

See more here:
Researchers improve CRISPR-Cas9 delivery efficiency - Drug Target Review

UK-based Oxford Nanopore has obtained a licence to CRISPR-Cas9 IP for nanopore sequencing, a third-generation approach used in the sequencing of biopolymers.

Oxford Nanopore, which specialises in DNA/RNA sequencing technology, announced the non-exclusive licence agreement with biotech company Caribou Biosciences yesterday, September 19.

Caribou was founded by scientists from the University of California, Berkeley, including CRISPR pioneer Jennifer Doudna.

Gordon Sanghera, CEO of Oxford Nanopore, said: The Cas9 technique will enable users to select and isolate the regions of the genome they are most interested in, including those not available to existing methods, ready for rapid analysis using our long-read, real-time sequencing technology.

According to the company, Cas9 enrichment with Oxford Nanopore sequencing enables scientists to cost-effectively sequence targeted regions that were not accessible previously.

Sanghera added: The entire library preparation process takes less than two hours so if combined with our portable sequencer MinION, this has the potential to open up fast-turnaround, near-sample testing in new ways.

In October last year, Amgen invested 50 million ($66 million) in Oxford Nanopore, as part of Amgens focus on using human genetics to deliver new medicines to patients.

Earlier in 2018, Oxford Nanopore announced it had raised 100 million from global investors, to be used to support the companys next phase of commercial expansion, including a new high-tech manufacturing facility in Oxford.

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Oxford Nanopore, CRISPR-Cas9, Caribou Biosciences, Jennifer Doudna, gene-editing, genetics, nanopore, University of California,

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Oxford Nanopore signs CRISPR licence - Life Sciences Intellectual Property Review

At this time, there is no cure for Duchenne muscular dystrophy (DMD), although there is one treatment for a subgroup of the disease. That is Sarepta Therapeutics Exondys 51 for DMD patients with a confirmed mutation amenable to exon 51 skipping. Recently the U.S. Food and Drug Administration (FDA) rejected Sareptas golodirsen for DMD with a confirmed mutation appropriate for exon 53 skipping.

DMD is a muscle wasting disease caused by mutations in the dystrophin gene. It is a progressive disease that usually causes death in early adulthood, with serious complications that include heart or respiratory-related problems. It mostly affects boys, about 1 in every 3,500 or 5,000 male children.

There just might be, however, hope for an actual cure. Researchers at the University of Missouri-Columbia, utilized CRISPR gene editing in a mouse model, to edit out the gene mutation and transplant AAV9 treated muscle into the mice. The transplanted muscle cells carried the edited gene and successfully produced dystrophin, the protein that is not produced in sufficient quantities in DMD patients.

The dystrophin gene is the largest in the body, and codes for the dystrophin protein, which is involved in muscle development and activity. One of the reasons DMD has been a tough nut to crack is that because of the genes size, its too large to fit into the typical viral vectors used in gene therapies. Thats partially why Sareptas approach is to use a type of RNA splicing that forces cells to skip over the faulty section of genetic code. This results in a shortened (truncated) protein that is still functional.

Research has shown that CRISPR can be used to edit out the nutation that causes the early death of muscle cells in an animal model, said Dongsheng Duan, the Margaret Proctor Mulligan Professor in Medical Research in the Department of Molecular Microbiology and Immunology at the MU School of Medicine and senior author of the study.

However, Duan went on, there is a major concern of relapse because these gene-edited muscle cells wear out over time. If we can correct the mutation in muscle stem cells, then cells regenerated from the edited stem cells will no longer carry the mutation. A one-time treatment of the muscle stem cells with CRISPR could result in continuous dystrophin expression in regenerated muscle cells.

Duans research, in collaboration with others at MU as well as the National Center for Advancing Translational Sciences, Johns Hopkins School of Medicine and Duke University, looked at whether muscle stem cells in mice could be effectively edited. They used AAV9, an adeno-associated virus recently approved by the FDA to treat spinal muscular atrophy (SMA)Novartis Zolgensma, which is also the source of the controversy over the companys data manipulation scandal.

They started by delivering CRISPR to normal mouse muscle via AAV9.

We transplanted AAV9-treated muscle into an immune-deficient mouse, said Michael Nance, an MD-PhD program student in Duans lab and the lead author of the paper. The transplanted muscle died first then regenerated from its stem cells. If the stem cells were successfully edited, the regenerated muscle cells should also carry the edited gene.

That appeared to work. They then tested if the muscle stem cells in the mice of DMD could be edited with CRISPRthey were.

This finding suggests that CRISPR gene editing may provide a method for lifelong correction of the genetic mutation in DMD and potentially other muscle diseases, Duan said. Our research shows that CRISPR can be used to effectively edit the stem cells responsible for muscle regeneration. The ability to treat the stem cells that are responsible for maintaining muscle growth may pave the way for a one-time treatment that can provide a source of gene-edited cells throughout the patients life.

The research was published in the journal Molecular Therapy.

More:
CRISPR Research Might Lead to Cure for Duchenne Muscular Dystrophy - BioSpace

Just because a business does not make any money, does not mean that the stock will go down. For example, although software-as-a-service business Salesforce.com lost money for years while it grew recurring revenue, if you held shares since 2005, you'd have done very well indeed. Nonetheless, only a fool would ignore the risk that a loss making company burns through its cash too quickly.

Given this risk, we thought we'd take a look at whether CRISPR Therapeutics (NASDAQ:CRSP) shareholders should be worried about its cash burn. In this article, we define cash burn as its annual (negative) free cash flow, which is the amount of money a company spends each year to fund its growth. The first step is to compare its cash burn with its cash reserves, to give us its 'cash runway'.

Check out our latest analysis for CRISPR Therapeutics

You can calculate a company's cash runway by dividing the amount of cash it has by the rate at which it is spending that cash. In June 2019, CRISPR Therapeutics had US$428m in cash, and was debt-free. In the last year, its cash burn was US$133m. That means it had a cash runway of about 3.2 years as of June 2019. Importantly, though, analysts think that CRISPR Therapeutics will reach cashflow breakeven before then. If that happens, then the length of its cash runway, today, would become a moot point. Depicted below, you can see how its cash holdings have changed over time.

NasdaqGM:CRSP Historical Debt, September 21st 2019

CRISPR Therapeutics boosted investment sharply in the last year, with cash burn ramping by 61%. That's bad enough, but the operating revenue drop of 96% points to a period of uncertainty and, quite potentially, heightened risk for holders." In light of the above-mentioned, we're pretty wary of the trajectory the company seems to be on. While the past is always worth studying, it is the future that matters most of all. So you might want to take a peek at how much the company is expected to grow in the next few years.

Even though it seems like CRISPR Therapeutics is developing its business nicely, we still like to consider how easily it could raise more money to accelerate growth. Companies can raise capital through either debt or equity. Commonly, a business will sell new shares in itself to raise cash to drive growth. We can compare a company's cash burn to its market capitalisation to get a sense for how many new shares a company would have to issue to fund one year's operations.

CRISPR Therapeutics has a market capitalisation of US$2.6b and burnt through US$133m last year, which is 5.1% of the company's market value. That's a low proportion, so we figure the company would be able to raise more cash to fund growth, with a little dilution, or even to simply borrow some money.

It may already be apparent to you that we're relatively comfortable with the way CRISPR Therapeutics is burning through its cash. For example, we think its cash runway suggests that the company is on a good path. Although we do find its falling revenue to be a bit of a negative, once we consider the other metrics mentioned in this article together, the overall picture is one we are comfortable with. It's clearly very positive to see that analysts are forecasting the company will break even fairly soon After considering a range of factors in this article, we're pretty relaxed about its cash burn, since the company seems to be in a good position to continue to fund its growth. For us, it's always important to consider risks around cash burn rates. But investors should look at a whole range of factors when researching a new stock. For example, it could be interesting to see how much the CRISPR Therapeutics CEO receives in total remuneration.

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Of course CRISPR Therapeutics may not be the best stock to buy. So you may wish to see this freecollection of companies boasting high return on equity, or this list of stocks that insiders are buying.

We aim to bring you long-term focused research analysis driven by fundamental data. Note that our analysis may not factor in the latest price-sensitive company announcements or qualitative material.

If you spot an error that warrants correction, please contact the editor at editorial-team@simplywallst.com. This article by Simply Wall St is general in nature. It does not constitute a recommendation to buy or sell any stock, and does not take account of your objectives, or your financial situation. Simply Wall St has no position in the stocks mentioned. Thank you for reading.

See more here:
CRISPR Therapeutics (NASDAQ:CRSP) Is In A Strong Position To Grow Its Business - Yahoo Finance

CRISPR is the buzzword of the moment in the drug discovery industry mainly due to its potential to correct disease-causing mutations. However, those using the technology need to be mindful that it is used responsibly, and possible risks are considered before use. Mark Behlke discusses the potential of CRISPR in R&D and the challenges that it presents for researchers.

CRISPR TECHNOLOGY has generated much excitement in the drug discovery realm for its ability to make precise, permanent changes to DNA in animals, as first demonstrated approximately six years ago. It is currently being evaluated in early phase clinical trials for several disorders. Diseases caused by a single gene mutation sickle cell disease (SCD), Huntingtons disease and cystic fibrosis are all prime targets for using CRISPR gene therapy to correct the disease-causing DNA mutations. CRISPR is also being investigated as a treatment for acquired immune deficiency syndrome (AIDS) and to improve anti-tumour immunotherapy.

While news about potential CRISPR therapeutics and the start of new clinical trials dominate headlines in the lay press, CRISPR has also become a leading research tool to help scientists better understand gene function and establish model systems of human diseases needed to translate basic scientific knowledge into new medical treatments.

Link:
The elegant parallel of using CRISPR to understand disease mechanisms - Drug Target Review

-New data demonstrate successful differentiation of CRISPR-edited human pluripotent stem cells to pancreatic precursor cells-

ZUG, Switzerland, CAMBRIDGE, Mass., and SAN DIEGO, Sept. 17, 2019 (GLOBE NEWSWIRE) -- CRISPR Therapeutics (CRSP), and ViaCyte, Inc., a privately-held cell therapy company, today presented data from the Companies regenerative medicine program targeted towards type 1 diabetes (T1D) in an oral presentation at the 55th Annual Meeting of the European Association for the Study of Diabetes (EASD) in Barcelona, Spain. The data demonstrate that the CyT49 pluripotent stem cell line, which has been shown to be amenable to efficient scaling and differentiation, can be successfully edited with CRISPR. The CyT49 pluripotent stem cell line is currently being used to generate islet progenitors for clinical trials.

These data provide further evidence that the combination of regenerative medicine and gene editing has the potential to offer durable, curative therapies to patients in many different diseases, including common chronic disorders like insulin-requiring diabetes, said Samarth Kulkarni, Ph.D., Chief Executive Officer of CRISPR Therapeutics. We look forward to advancing our T1D program in partnership with ViaCyte.

We are pleased with the data presented at EASD, which bring us potentially one step closer to a transformational therapy for patients with insulin-requiring diabetes through the development of an immune-evasive gene-edited version of our technology, said Paul Laikind, Ph.D., Chief Executive Officer and President of ViaCyte. ViaCyte has led the field over the past decade, being the first group to demonstrate a number of essential milestones on the path to a broadly applicable cell replacement therapy for diabetes. Now, in partnership with CRISPR Therapeutics, we aim to achieve yet another first, the development of an immune-evasive cell replacement therapy as a potential cure for T1D. The work being presented at EASD is an important step along that path.

To protect pancreatic islet cells from immune rejection, researchers utilized CRISPR/Cas9 gene editing to generate CyT49 clones that lack the 2-microglobulin (B2M) gene, a required component of the major histocompatibility complex class I (MHC-I), and express a transgene encoding programmed death-ligand 1 (PD-L1) to further protect from T-cell attack. Edited clonal cells maintained karyotypic stability and showed in vitro protection against T-cell mediated cell lysis.

About the CRISPR-ViaCyte CollaborationCRISPR Therapeutics and ViaCyte entered into a strategic collaboration in 2018 focused on the discovery, development, and commercialization of novel regenerative medicines including gene-edited allogeneic stem cell-derived therapies for the treatment of diabetes. The Companies are currently evaluating a preclinical-stage therapeutic candidate for insulin-requiring diabetes including type 1 diabetes, for which the Companies will jointly assume responsibility for development and commercialization worldwide.

About CRISPR TherapeuticsCRISPR Therapeutics is a leading gene editing company focused on developing transformative gene-based medicines for serious diseases using its proprietary CRISPR/Cas9 platform. CRISPR/Cas9 is a revolutionary gene editing technology that allows for precise, directed changes to genomic DNA. CRISPR Therapeutics has established a portfolio of therapeutic programs across a broad range of disease areas including hemoglobinopathies, oncology, regenerative medicine and rare diseases. To accelerate and expand its efforts, CRISPR Therapeutics has established strategic collaborations with leading companies including Bayer AG, Vertex Pharmaceuticals and ViaCyte, Inc. CRISPR Therapeutics AG is headquartered in Zug, Switzerland, with its wholly-owned U.S. subsidiary, CRISPR Therapeutics, Inc., and R&D operations based in Cambridge, Massachusetts, and business offices in London, United Kingdom. For more information, please visit http://www.crisprtx.com.

About ViaCyteViaCyte is a privately-held regenerative medicine company developing novel cell replacement therapies as potential long-term diabetes treatments to achieve glucose control targets and reduce the risk of hypoglycemia and diabetes-related complications. ViaCytes product candidates are based on the derivation of pancreatic isletprogenitor cells from pluripotent stem cells, which are then implanted in durable and retrievable cell delivery devices. Over a decade ago, ViaCyte scientists were the first to report on the production of pancreatic cells from a stem cell starting point and the first to demonstrate in an animal model of diabetes that, once implanted and matured, these cells secrete insulin and other pancreatic hormones in response to blood glucose levels. ViaCyte has two product candidates in clinical-stage development. The PEC-Direct product candidate delivers the pancreatic isletprogenitor cells in a non-immunoprotective device and is being developed for type 1 diabetes patients who have hypoglycemia unawareness, extreme glycemic lability, and/or recurrent severe hypoglycemic episodes. The PEC-Encap (also known as VC-01) product candidate delivers the same pancreatic isletprogenitor cells in an immunoprotective device and is being developed for all patients with diabetes, type 1 and type 2, who use insulin. ViaCyte is also developing immune-evasive stem cell lines, from its proprietary CyT49 cell line, which have the potential to further broaden the availability of cell therapy for diabetes and other potential indications. ViaCyte is headquartered in San Diego, California. ViaCyte is funded in part by the California Institute for Regenerative Medicine (CIRM) and JDRF. For more information, please visit http://www.viacyte.com.

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CRISPR Forward-Looking StatementThis press release may contain a number of forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, as amended, including statements regarding CRISPR Therapeutics expectations about any or all of the following: (i) the safety, efficacy and clinical progress of our various clinical programs including CTX001 and CTX110; (ii) the status of clinical trials (including, without limitation, the timing of filing of clinical trial applications and INDs, any approvals thereof and the timing of commencement of clinical trials), development timelines and discussions with regulatory authorities related to product candidates under development by CRISPR Therapeutics and its collaborators; (iii) the number of patients that will be evaluated, the anticipated date by which enrollment will be completed and the data that will be generated by ongoing and planned clinical trials, and the ability to use that data for the design and initiation of further clinical trials; (iv) the intellectual property coverage and positions of CRISPR Therapeutics, its licensors and third parties as well as the status and potential outcome of proceedings involving any such intellectual property; (v) the sufficiency of CRISPR Therapeutics cash resources; and (vi) the therapeutic value, development, and commercial potential of CRISPR/Cas9 gene editing technologies and therapies. Without limiting the foregoing, the words believes, anticipates, plans, expects and similar expressions are intended to identify forward-looking statements. You are cautioned that forward-looking statements are inherently uncertain. Although CRISPR Therapeutics believes that such statements are based on reasonable assumptions within the bounds of its knowledge of its business and operations, forward-looking statements are neither promises nor guarantees and they are necessarily subject to a high degree of uncertainty and risk. Actual performance and results may differ materially from those projected or suggested in the forward-looking statements due to various risks and uncertainties. These risks and uncertainties include, among others: the potential for initial and preliminary data from any clinical trial (including CTX001 and CTX110) not to be indicative of final trial results; the risk that the initial data from a limited number of patients (as is the case with CTX001 at this time) may not be indicative of results from the full planned study population; the outcomes for each CRISPR Therapeutics planned clinical trials and studies may not be favorable; that one or more of CRISPR Therapeutics internal or external product candidate programs will not proceed as planned for technical, scientific or commercial reasons; that future competitive or other market factors may adversely affect the commercial potential for CRISPR Therapeutics product candidates; uncertainties inherent in the initiation and completion of preclinical studies for CRISPR Therapeutics product candidates; availability and timing of results from preclinical studies; whether results from a preclinical trial will be predictive of future results of the future trials; uncertainties about regulatory approvals to conduct trials or to market products; uncertainties regarding the intellectual property protection for CRISPR Therapeutics technology and intellectual property belonging to third parties, and the outcome of proceedings (such as an interference, an opposition or a similar proceeding) involving all or any portion of such intellectual property; and those risks and uncertainties described under the heading "Risk Factors" in CRISPR Therapeutics most recent annual report on Form 10-K, and in any other subsequent filings made by CRISPR Therapeutics with the U.S. Securities and Exchange Commission, which are available on the SEC's website at http://www.sec.gov. Existing and prospective investors are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date they are made. CRISPR Therapeutics disclaims any obligation or undertaking to update or revise any forward-looking statements contained in this press release, other than to the extent required by law.

CRISPR Investor Contact:Susan Kim+1 617-307-7503susan.kim@crisprtx.com

CRISPR Media Contact:Jennifer PaganelliWCG on behalf of CRISPR+1 347-658-8290jpaganelli@wcgworld.com

ViaCyte Investor Contact: Matthew LaneGilmartin Group on behalf of ViaCyte, Inc. +1 617-901-7698matt@gilmartinir.com

ViaCyte Media Contact:Jessica Yingling, Ph.D. Little Dog Communications Inc. on behalf of ViaCyte, Inc. +1 858-344-8091jessica@litldog.com

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CRISPR Therapeutics and ViaCyte Present Positive In Vitro Data Towards a Potential Immune-Evasive Cell Replacement Therapy for Diabetes at EASD 2019 -...

CRISPR may be a cure, but clinical trials may lack volunteers because of black patients' mistrust of biased and unethical medical practices.

"It's like something stabbing you in your bone just like repeatedly. And you can't stop it. And... it's something that makes you really tense, you just can't move... It's been a part of my life since I was six months old."

Twenty-three-year-old Maiya Washington has been living with sickle cell, a life-long "invisible" disease. It's a disorder with no visibly detectable signs and not often talked about.

"Although it is a disease that is invisible, so to speak, we go through a lot, you know, and we go through a lot to be normal to live life to get jobs to go to school. And it's hard. It's really hard," says Washington.

Sickle Cell Disease impacts about100,000 Americans,mostly African Americans. It's a genetic defect that affects red blood cells turning normal round red blood cells into sickle shapes. That shape can cause clumping andblock oxygen and blood flow,which can then lead to a wide range of health issues likestrokes, kidney problems,and organ failure.

"It's really debilitating, honestly," says Washington. "And it's hard because... you need somebody there with you. It's not like you can take yourself to the hospital. Or if you're at home and you're trying to manage the pain by yourself, you still need somebody there with you, because you're not able to do the simple things like go to the restroom by yourself, get yourself some water, fix yourself something to eat"

Currently, the only option to cure sickle cell disease is a bone marrow transplant, also called a stem cell transplant. But it requires a matching donor, which can be difficult to find. But now, the gene-editing tool CRISPR may bypass the need for a match and serve as a cure for most people. Dr. John Tisdale has worked on another Sickle Cell Disease gene therapy at the National Institute of Health.

"And it's all coming from red blood cells with a single misspelling, in their hemoglobin. So we should be able to fix that it's just one base," says Tisdale.

Related StoryIs The Machine That Can Snip And Swap Our DNA Awesome Or Ominous?

Here's how it works. First, stem cells are pulled from the patient's body. CRISPR is used to edit the DNA, and the new, edited stem cells are then re-inserted back into the body. The hope is that it will generate healthy red blood cells. Changes to the DNA won't be passed down to future children.

Could this development lead to a cure for sickle cell? A clinical trial using CRISPR can help determine that. So far, testing on 12 people has already begun. Biopharmaceutical company Vertex has partnered with CRISPR Therapeutics and they're looking for morevolunteers for this clinical trial.

Dr. Alexis Thompson, Head of Hematology, Lurie Childrens Hospital of Chicago says, "I certainly am very excited about it as a provider, is that patients will have choices. There is not a one size fits all for sickle cell disease, or really, really for in a community For the first time, there will be multiple, multiple clinical trials that are opening and hopefully those will lead to new treatments... because much of what we learn from sickle cell will be rapidly applicable to other conditions."

But as exciting as the potential for a cure for Sickle Cell Disease is, finding enough volunteers for testing is really difficult. Sure, CRISPR poses risks, including death. But one of the biggest barriers isblack patients' mistrust of the medical community,so much so that clinical trialstend to lack black patient enrollment.This is based on racist treatment both in the past and present.Science writer Usha Lee MacFarlingpoints to unethical medical practices of the past, like the use of Henrietta Lacks' cells without permission and leaving syphilis untreated in hundreds of black men in the Tuskegee experiment.

"I think there's just a huge awareness in the black community of these studies that were, you know, racist, that really treated black women of color and poor women as guinea pigs. It's a very sharp pain And it's definitely affecting people's reluctance, and inability to trust, the largely white medical establishment," says MacFarling.

And today, some black patients say that bias persists in medicine. Because sickle cell patientsvisit the emergency room an average of three times a year, they're often assumed to be addicts for seeking drugs to ease their pain.

Related StoryResearchers' Gene Technology Removes HIV From Mice For The First Time

"Doctors [have]...given me an inappropriate amount of medicine. That wasn't helping, that kind of basically looked at me as like, you know, drug-seeking, or just like faking it," says Washington.

In spite of all this, Maiya says she wants to participate in the trial because of how excruciating her pain is.

"I feel as though most people who deal with sickle cell or any kind of disability that alters their quality of life, they're going to be willing to figure out anything to get rid of what they had," says Washington.

In order to build trust between black sickle cell patients and CRISPR researchers, organizations like the American Society of Hematology and the Minority Coalition for Precision Medicine are doing community outreach. That includes even teaming up with churches.

Michael Friend, co-founder of Minority Coalition for Precision Medicine says: "It was kind of very easy to talk to faith-based leaders about sickle cell disease because it's a disease that primarily affects African Americans. And it's a disease that we found prevalent in most churches, and most pastors were familiar with the disease."

Related StoryScientists Concerned Over Program That Enlists Bugs To Spread Viruses

For now, every month Maiya's gets a blood transfusion to ease the pain. Her baby is lucky -- she doesn't have sickle cell, because her father doesn't have the gene.

"I wake up every day and she's there. She's my best friend and I love seeing her watching her grow so far, says Washington.

Most sickle cell patients don't live past their 40's and Maiya does worry about her future.

She says, "it does concern me because I want to be here as long as possible for her. And hoping that, you know, there's something that can come up that can be permanent, you know, as in terms of a cure or medication...just to help us have a longer lifespan and live a better quality of life. Because I do want to be able to see her grow up."

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CRISPR Cure For Sickle Cell May Be Slowed By Black Patients' Mistrust - Newsy

We are at war with the mosquito. A swarming and consuming army of 110tn enemy mosquitoes patrols every inch of the globe except for Antarctica, Iceland and a handful of French Polynesian micro-islands. The biting female warrior of this droning insect population is armed with at least 15 lethal and debilitating biological weapons, to be used against 7.7 billion humans deploying suspect and often self-detrimental defensive capabilities. In fact, our defence budget for personal shields, sprays and other means of deterring her unrelenting raids is $11bn (8.8bn) a year, and rising rapidly. And yet her deadly offensive campaigns and crimes against humanity continue with reckless abandon. While our counterattacks are reducing the number of casualties she perpetrates malaria deaths in particular are declining rapidly the mosquito remains the deadliest hunter of human beings on the planet.

Taking a broad range of estimates into account, since 2000, the average annual number of human deaths caused by the mosquito was around 2 million. Humans came in a distant second at 475,000, followed by snakes (50,000), dogs and sandflies (25,000 each), the tsetse fly, and the assassin or kissing bug (10,000 each). The fierce killers of lore and Hollywood celebrity were much further down our list. The crocodile was ranked 10th, with 1,000 annual deaths. Next on the list were hippos with 500, and elephants and lions with 100 fatalities each. The much-slandered shark and wolf shared 15th position, killing an average of 10 people per annum.

Yet the mosquito does not directly harm anyone. It is the toxic and highly evolved diseases she transmits that cause an endless barrage of desolation and death. Without her, however, these sinister pathogens could not be transferred or vectored to humans, nor could they continue their cyclical contagion. In fact, without her, these diseases would not exist at all.

Our immune systems are finely tuned to our local environments. Mosquitoes do not respect international borders. Marching armies, inquisitive explorers and land-hungry colonists brought new diseases to distant lands, but were also brought to their knees by micro-organisms in the foreign lands they intended to conquer. As the mosquito transformed the landscapes of civilisation, humans were unwittingly required to respond to her universal projection of power. After all, the truth is that, more than any other external participant, the mosquito, as our deadliest predator, drove the events of human history to create our present reality.

It has been one of the most universally recognisable and aggravating sounds on Earth for 190m years the whine of a mosquito. After a long day of walking while camping with your family or friends, you quickly shower, settle into your lawn chair, open an ice-cold beer and exhale a deep, contented sigh. Before you can enjoy your first satisfying swig, however, you hear that all-too-familiar sound, signalling the approach of your soon-to-be tormentors.

It is nearing dusk, her favourite time to feed. Although you heard her droning arrival, she gently lands on your ankle without detection, as she usually bites close to the ground. It is always a female, by the way. She conducts a tender, probing, 10-second reconnaissance, looking for a prime blood vessel. With her backside in the air, she steadies her crosshairs and zeros in with six sophisticated needles. She inserts two serrated mandible cutting blades (much like an electric carving knife, with two blades shifting back and forth), and saws into your skin, while two other retractors open a passage for the proboscis, a hypodermic syringe that emerges from its protective sheath. With this straw she starts to suck out 3-5 mg of your blood, immediately excreting its water while condensing its 20% protein content. All the while, a sixth needle is pumping in saliva that contains an anticoagulant, preventing your blood from clotting at the puncture site. This shortens her feeding time, lessening the likelihood that you feel her penetration and splat her across your ankle. The anticoagulant causes an allergic reaction, leaving an itchy bump as her parting gift. The mosquito bite is an intricate and innovative feeding ritual required for reproduction. She needs your blood to grow and mature her eggs.

Please dont feel singled out. She bites everyone. There is absolutely no truth to the persistent myths that mosquitoes fancy females over males, that they prefer blonds and redheads over those with darker hair, or that the darker or more leathery your skin, the safer you are from her bite. It is true, however, that she does play favourites and feasts on some more than others. Blood type O seems to be the vintage of choice over types A and B, or their blend. People with blood type O get bitten twice as often as those with type A, with type B falling somewhere in between. (Disney/Pixar must have done their homework when portraying a tipsy mosquito ordering a Bloody Mary, O-positive in the 1998 movie A Bugs Life.) Those who have higher natural levels of certain chemicals in their skin, particularly lactic acid, also seem to be more attractive. From these elements, she can analyse which blood type you are. These are the same chemicals that determine an individuals level of skin bacteria and unique body odour. While you may offend others and perhaps yourself, in this case, being pungently rancid is a good thing, for it increases bacterial levels on the skin, which makes you less alluring to mosquitoes except for stinky feet, which emit a bacterium that is a mosquito aphrodisiac. The mosquito is also enticed by deodorants, perfumes, soap and other applied fragrances.

She also has an affinity for beer drinkers. Wearing bright colours is also not a wise choice, since she hunts by both sight and smell the latter depending chiefly on the amount of carbon dioxide exhaled by the potential target. So all your thrashing and huffing and puffing only magnetises mosquitoes and puts you at greater risk. She can smell carbon dioxide from 200 feet away. When you exercise, you emit more carbon dioxide through frequency of breath and output. You also sweat, releasing those appetising chemicals, primarily lactic acid, that invite the mosquitos attention. Lastly, your body temperature rises an easily identifiable heat signature. On average, pregnant women suffer twice as many bites, as they respire 20% more carbon dioxide, and have a marginally elevated body temperature. This is bad news for the mother and the foetus when it comes to infection from Zika and malaria.

Unlike their female counterparts, male mosquitoes do not bite. Their world revolves around two things: nectar and sex. Like other flying insects, when they are ready to mate, male mosquitoes assemble over a prominent feature in the landscape from chimneys to antennas to trees to people. Many of us grumble and flail in frustration as that dogged cloud of bugs droning over our heads shadows us when we walk, refusing to disperse. Take it as a compliment. Male mosquitoes have graced you with the honour of being a swarm marker. Mosquito swarms have been photographed extending 1,000 feet into the air, resembling a tornado funnel cloud. With the cocksure males stubbornly assembled over your head, females will fly into their horde to find a suitable mate. While males will mate frequently in a lifetime, one dose of sperm is all the female needs to produce numerous batches of offspring. She stores the sperm and dispenses them piecemeal for each separate birthing of eggs. Her short moment of passion has provided one of the two necessary components for procreation. The only ingredient missing is your blood.

Back at the campsite, you have just finished your strenuous hike, and proceed to the shower, where you lather up with soap and shampoo. After drying off, you apply body spray and deodorant before finally putting on your bright red-and-blue beachwear.

It is nearing dusk dinnertime for the Anopheles mosquito. You have done everything in your power to lure a famished female of the species. Having just mated in a swarming frenzy of eager male suitors, she willingly takes the bait and makes off with a few drops of your blood a blood meal three times her own body weight. She quickly finds the nearest vertical surface and, with the aid of gravity, continues to evacuate the water from your blood. Using this concentrated blood, she will develop her eggs over the next few days. She then deposits roughly 200 floating eggs on the surface of a small pool of water that has collected on a crushed beer can that was overlooked during cleanup as you and your party headed home. She always lays her eggs in water, although she does not need much. From a pond or stream to a minuscule puddle in the bottom of an old container, used tire or backyard toy, any will suffice.

Our mosquito will continue to bite and lay eggs during her one-to-three-week lifespan. While she can fly up to two miles, she rarely ranges more than 400 metres from her birthplace. Although it takes a few days longer in cool weather, given the high temperatures, her eggs hatch into wiggling, water-bound worms within two or three days. Skimming the water for food, they quickly turn into upside-down, comma-shaped tumbling caterpillars who breathe through two trumpets protruding from their water-exposed buttocks. A few days later, a protective encasement splits and healthy adult mosquitoes take flight, with a new generation of succubus females ready to feed. This maturation to adulthood takes roughly one week.

Bacteria, viruses and parasites, along with worms and fungi, have triggered untold misery, and have commanded the course of human history. Why have these pathogens evolved to exterminate their hosts? If we can set aside our bias for a moment, we can see that these microbes have journeyed through the natural selection voyage just as we have. This is why they still make us sick and are so difficult to eradicate. You may be puzzled: it seems self-defeating and detrimental to kill your host. The disease kills us, yes, but the symptoms of the disease are ways in which the microbe conscripts us to help it spread and reproduce. It is dazzlingly clever, when you stop to think about it. Generally, germs guarantee their contagion and replication prior to killing their hosts. Some, like the salmonella food poisoning bacteria and various worms, wait to be ingested that is, one animal eating another animal.

There is a wide range of waterborne transmitters, including giardia, cholera, typhoid, dysentery and hepatitis. Others, including the common cold, the 24-hour flu and true influenza, are passed on through coughing and sneezing. Some, such as smallpox, are transferred directly or indirectly by lesions, open sores, contaminated objects or coughing. My personal favourites strictly from an evolutionary standpoint, of course are those that covertly ensure their reproduction while we intimately ensure our own. These include the full gamut of microbes that trigger sexually transmitted diseases. Many sinister pathogens are passed from mother to foetus in utero.

Others that germinate typhus, bubonic plague, Chagas and trypanosomiasis (African sleeping sickness) catch a free ride provided by a vector (an organism that transmits disease) such as fleas, mites, flies, ticks and mosquitoes. To maximise their chances of survival, many germs use a combination of more than one method. The diverse collection of symptoms, or modes of transference, assembled by micro-organisms helps them effectively procreate and ensures the existence of their species. These germs fight for their survival just as much as we do, and stay an evolutionary step ahead of us as they continue to morph and shape-shift to circumvent our best means of extermination.

To understand the stealthy, sprawling influence of the mosquito on history and humanity, it is first necessary to appreciate the animal itself, and the diseases it transmits. According to a quotation erroneously attributed to Charles Darwin: It is not the strongest of the species that survives, nor the most intelligent that survives. It is the one that is most adaptable to change. Regardless of the origin of this passage, the mosquito and its diseases most notably malaria parasites are the quintessential example of the point it is making. They are masters of evolutionary adaptation. Mosquitoes can evolve and adapt to their changing environments within a few generations. During the Blitz of 1940-41, for example, as German bombs rained down on London, isolated populations of Culex mosquitoes were confined to the air-raid tunnel shelters of the London Underground, along with the citys resilient citizens. These trapped mosquitoes quickly adapted to feed on mice, rats and humans instead of birds, and are now a species distinct from their above-ground parental ancestors.

What should have taken thousands of years of evolution was accomplished in less than 100. In another 100 years, jokes Richard Jones, former president of the British Entomological and Natural History Society, there may be separate Circle line, Metropolitan line and Jubilee line mosquito species in the tunnels below London.

While the mosquito is miraculously adaptable, it is also a purely narcissistic creature. Unlike other insects, it does not pollinate plants in any meaningful way, or aerate the soil, or ingest waste. Contrary to popular belief, the mosquito does not even serve as an indispensable food source for any other animal. She has no purpose other than to propagate her species, and perhaps to kill humans. As the apex predator throughout our odyssey, it appears that her role in our relationship is to act as a countermeasure against uncontrolled human population growth.

Throughout our existence, the mosquitos toxic twins of malaria and yellow fever have been the prevailing agents of death and historical change, playing the role of antagonists in the protracted chronological war between man and mosquito.

Following that fateful mosquito bite, the miscreant malaria parasite will mutate and reproduce inside your liver for one to two weeks, during which time you will show no symptoms. A toxic army of this new mutated form will then explode out of your liver and invade your bloodstream. The parasites attach to your red blood cells, penetrate the outer defences, and feast on the haemoglobin within. Inside the cell, they undergo another metamorphosis and reproductive cycle. Engorged blood cells eventually burst, spewing both a duplicate form, which marches forward to attack fresh red blood cells and also a new asexual form that relaxedly floats in your bloodstream, waiting for mosquito transportation.

The parasite is a shape-shifter, and it is precisely this genetic flexibility that makes it so difficult to eradicate or suppress with drugs or vaccines. You are now gravely ill with an orderly, clockwork progression of chills followed by a mercury-driving fever that may touch 41C. This full-blown cyclical malarial episode has you in its firm grip, and you are at the mercy of the parasite. Lying prostrate and agonisingly helpless on sweat-soaked sheets, you twitch and fumble, curse and moan. You look down and notice that your spleen and liver are visibly enlarged, your skin has the yellowing patina of jaundice and you vomit sporadically. Your fever will relapse at precise intervals with each new burst and invasion of the parasite from your blood cells. The fever then subsides while the parasite eats and reproduces inside new blood cells.

The parasite uses sophisticated signalling to synchronise its sequencing, and this entire cycle adheres to a very strict schedule. The new asexual form transmits a chemical bite me signal in our blood, significantly boosting the chances of being picked up by a mosquito from an infected human to complete the reproductive cycle. Inside the stomach of the mosquito, these cells mutate once more, into both male and female varieties. They quickly mate, producing threadlike offspring that make their way out of the gut and into the salivary glands of the mosquito. Within the saliva glands, the malaria parasite shrewdly manipulates the mosquito to bite more frequently by suppressing the production of her anticoagulant and thus minimising her blood intake during a single feeding. This forces her to bite more frequently to get her required fill. In doing so, the malaria parasite ensures that it maximises its rate and range of transfer, its procreation and its survival.

Temperature is an important element for both mosquito reproduction and the life cycle of malaria. Given their symbiotic relationship, they are also both climate-sensitive. In colder temperatures, it takes longer for mosquito eggs to mature and hatch. Mosquitoes are also cold-blooded and, unlike mammals, cannot regulate their own body temperatures. They simply cannot survive in environments below 10C. Mosquitoes are generally at their prime health and peak performance in temperatures above 23C. A direct heat of 40C degrees will boil mosquitoes to death. For temperate, non-tropical zones, this means that mosquitoes are seasonal creatures with breeding, hatching and biting taking place from spring through autumn. Although never seeing the outside world, malaria needs to contend with both the short lifespan of the mosquito and temperature conditions to ensure replication. The timeframe of malaria reproduction is dependent on the temperature of the cold-blooded mosquito, which itself is dependent on the temperature outside. The colder the mosquito, the more sluggish malaria reproduction becomes, eventually hitting a threshold. Between 15C and 21C (depending on the type of malaria), the reproductive cycle of the parasite can take up to a month, exceeding the average life span of the mosquito. By then, she is long dead, and brings malaria down with her.

Warmer climates can sustain year-round mosquito populations, promoting endemic circulation of her diseases. Abnormally high temperatures can cause seasonal epidemics of mosquito-borne diseases in regions where they are generally absent or fleeting. Global warming also allows the mosquito and her diseases to broaden their topographical range. As temperatures rise, disease-carrying species, usually confined to southern regions and lower altitudes, creep north and into higher elevations.

Since a breakthrough discovery by a team led by the biochemist Dr Jennifer Doudna at the University of California, Berkeley in 2012, the revolutionary gene-editing innovation known as Crispr has shocked the world and altered our preconceived notions about our planet and our place on it.

The pages of many widely read magazines and journals are currently consumed by the topic of Crispr and mosquitoes. First successfully used in 2013, Crispr is a procedure that snips out a section of DNA sequencing from a gene and replaces it with another desired one, permanently altering a genome, quickly, cheaply, and accurately.

The Bill and Melinda Gates Foundation has been funding research into mosquito-borne diseases since its creation in 2000. In 2016 it made investments in Crispr mosquito research totalling $75m. Our investments in mosquito control, said the foundation, include nontraditional biological and genetic approaches as well as new chemical interventions aimed at depleting or incapacitating disease-transmitting mosquito populations. These genetic approaches include the use of Crispr machinery to eradicate mosquito-borne diseases, most notably malaria.

The strategic goal of the Gates Foundation is the extermination of malaria and other mosquito-borne diseases; it is not to bring the mosquito which is harmless when flying solo, untethered from a hitchhiking micro-organism to the brink of extinction. Of the more than 3,500 mosquito species, only a few hundred are capable of vectoring disease. Prefabricated, genetically modified mosquitoes rendered incapable of harbouring the parasite (a hereditary trait passed down their bloodline) might just end the timeless scourge of malaria. But, as Doudna and the Gates Foundation are aware, gene-swapping technology also has the potential to unleash darker, more sinister genetic blueprints with dangerous possibilities. Crispr research is a global phenomenon, and neither Doudna nor the foundation has a monopoly on its limitless designs, its instruments of implementation or its operational execution.

It has been dubbed the extinction drive, as this is precisely what it can accomplish the extermination of mosquitoes by way of genetic sterilisation. This theory has been floating around the scientific community since the 1960s. Crispr can now put these principles into practice. To be fair, the mosquito altered our DNA in the form of sickle cell and other genetic malarial safeguards; perhaps it is time to return the favour. Male mosquitoes that have been genetically modified with domineering selfish genes using Crispr are released into mosquito zones to breed with females to produce stillborn, infertile or only male offspring. The mosquito would be extinct in one or two generations. With this war-winning weapon, humanity would never again have to fear the bite of a mosquito. We would awaken to a brave new world, one without mosquito-borne disease.

An alternative is simply to make mosquitos harmless, a strategy supported and funded by the Gates Foundation. With gene drive technology, Gates explained in October 2018, essentially, scientists could introduce a gene into a mosquito population that would either suppress the population or prevent it from spreading malaria. For decades, it was difficult to test this idea. But with the discovery of Crispr, the research became a lot easier. And just last month, a team from the research consortium Target Malaria announced that they had completed studies where mosquito populations were fully suppressed. To be clear: the test was only in a series of laboratory cages filled with 600 mosquitoes each. But it is a promising start.

Dr Anthony James, a molecular geneticist at the University of California, Irvine, Crisprd a species of Anopheles mosquito to make it incapable of spreading malaria, by eliminating the parasites as they are processed through the mosquitos salivary gland. We added a small package of genes, explains James, that allows the mosquitoes to function as they always have, except for one slight change they can no longer harbour the malaria parasite.

The Aedes breed is more difficult to tackle, since it transmits a handful of diseases that include yellow fever, Zika, West Nile, chikungunya, Mayaro, dengue and other encephalitides. What you need to do is engineer a gene drive that makes the insects sterile, James said of the Aedes breed. It doesnt make sense to build a mosquito resistant to Zika if it could still transmit dengue and other diseases.

We have valid, although yet unknown, reasons to be careful what we wish for. If we eradicate disease-vectoring mosquito species, would other mosquito species or insects simply fill the ecological niche? What effect would eliminating mosquitoes have on natures biological equilibrium? What would happen if we exterminate species that play an essential but unrecognised role in our ecosystem? We are just beginning to ask these morally fraught and biologically ambiguous questions, and for now, no one really knows the answers.

This is an edited extract from The Mosquito: A Human History of Our Deadliest Predator by Timothy Winegard, published by Text on 26 September and available at guardianbookshop.co.uk

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People v mosquitos: what to do about our biggest killer - The Guardian

The gene drive is one of the latest of advancements in genetic modification of living things. It may also be the most controversial, in a field that has seen more than its fair share of controversy. Traditionally, coverage of genetic modifications in food products has resembled war correspondence:

Side 1Gene drives are a valuable tool for controlling pests and perpetuating beneficial genes through agricultural productsSide 2Gene drives are a dangerous, untested and unnatural genetic changes created to deliberately drive a species to extinction.

Gene drive is a version of gene editinga newer, more precise way to change a DNA (or RNA) sequence, in this case by combining a guide RNA with an enzyme that can make a splice in the exact place where a sequence can be removed, another sequence inserted, or the existing sequence altered. Gene drive takes this to another level, making sure that a new or altered genetic sequence has a greater than 50 percent chance of being inherited. This can be done in a number of ways, some of which already exist in nature, some which are no different than traditional gene editing using CRISPR-Cas9, and others that have triggered a backlash from environmental activist groupsnon-governmental organizations (NGOs) that utilize fear for their own political ends.

So far, this debate has pitted NGOs like Friends of the Earth, Greenpeace and ETC Group (who are opposed to any genetic manipulations in food crops and animals) against scientists, some agricultural companies and even some government regulators (almost all of whom conclude that these products are no more dangerous than those developed through traditional breeding).

The activist effort is part of a long-standing campaign to conflate gene drives, gene editing and traditional transgenics (GMO) as the same technology, with the same scientific certainty (or uncertainty) and risks. In 2016, FOE and others asked for a worldwide moratorium on gene drives:

Gene drives, developed through new gene-editing techniques, are designed to force a particular genetically engineered trait to spread through an entire wild population potentially changing entire species or even causing deliberate extinctions. The statement urges governments to put in place an urgent, global moratorium on the development and release of the new technology, which poses serious and potentially irreversible threats to biodiversity, as well as national sovereignty, peace and food security.

Many times, these activist organizations have claimed the public shares their concerns. Citing survey data, the science community has retorted that most people embrace biotechnology when they recognize that it benefits them directly. But what has been missing from the battle between the pro- and anti-GMO positions is a scientific measure of public opinion on more recent techniques such as gene drive. In 2016, a comprehensive National Academies of Science (NAS) report called for not only continued research on the effectiveness and usefulness of gene drives, but also their ecological risks and engagement with the public. While institutions like FOE and ETC Group objected to the existence of gene drives, they did not represent the opinion of the public.

For the first time, that opinion was actually tested, by researchers at North Carolina State University and the University of Wisconsin. In a paper published in Science Advances, Zack Brown, assistant professor of resource economics at NC State and his colleagues surveyed 1,000 American adults on their opinions of gene drives. What they found, instead of opposition, was support for the technology, with a few caveats:

The survey results could be valuable in this early stage of gene drive (or gene editing, for that matter) development as research could possibly be directed toward designing drive strategies that could incorporate controlsnot an easy thing to do, Brown said in a press release.

This is the right timewhile the technology is still under development and before any release decisions have been madeto gain insights into what the public thinks, what types of information they prioritize from researchers, and who is trusted to carry out this sensitive research, said Michael Jones, a graduate student at NC State and co-author of the published survey results.

Another significant finding in the NC State/Wisconsin study was that Americans surveyed trusted universities and the US Department of Agriculture (USDA) (60 percent) over foreign universities, the US Department of Defense (18 percent) and private companies (16 percent) to research gene drive systems.

The survey did not ask respondents for their trust levels of NGOs like FOE and Greenpeace.

However, in another recently published survey, this one in Current Research in Biotechnology, 113 experts (scientists, government officials, agribusiness professionals) found that gene-edited crops posed little to no risk to society, the economy, human health or the environment. Less than five percent thought the techniques posed a high risk.

The experts, most of whom observed that NGOs generally opposed gene editing, gene drive and any other genetic modification, noted that this opposition is based on speculative risks, those that have no established theory or evidence data. The authors of the study, based at the University of Saskatchewan in Canada, warned that the problem with attempting to reconcile speculative risks with risks grounded in theory and evidence, is that speculative risks can be very fluid and dynamic, changing at will and [frequently] at the whim of eNGO political motives.

These new studies seem to support the idea that consumers are less wary of biotechnology when they know how its being deployed. While public opinion surveys show support with some caveats about taking precautions against accidents and outbreaks, by and large members of the public trust scientists, particularly those in academia and at relevant regulatory agencies to navigate this controversial but promising field of research.

Andrew Porterfield is a writer and editor, and has worked with numerous academic institutions, companies and non-profits in the life sciences.BIO. Follow him on Twitter@AMPorterfield

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Viewpoint: Public supports CRISPR, gene drives to battle infectious disease, plant pestsdespite activist opposition - Genetic Literacy Project

Scientists are reporting the first use of the gene-editing tool CRISPR to try to cure a patients HIV infection by providing blood cells that were altered to resist the AIDS virus.

The gene-editing tool has long been used in research labs, and a Chinese scientist was scorned last year when he revealed he used it on embryos that led to the birth of twin girls. Editing embryos is considered too risky, partly because the DNA changes can pass to future generations.

Wednesdays report in the New England Journal of Medicine, by different Chinese researchers, is the first published account of using CRISPR to treat a disease in an adult, where the DNA changes are confined to that person.

The attempt was successful in some ways but fell short of being an HIV cure.

Still, it shows that gene editing holds promise and seems precise and safe in this patient so far, said Dr. Carl June, a University of Pennsylvania genetics expert who wrote a commentary in the journal.

Thats really good for the field, June said.

Chinese government grants paid for the research, which was done openly with advance notice on a scientific registry and standard informed consent procedures. Some of those steps were missing or questioned in last years embryo work.

There are no ethical concerns on this one, June said.

Gene editing permanently alters DNA, the code of life. CRISPR is a relatively new tool scientists can use to cut DNA at a specific spot.

The new case involves a 27-year-old man with HIV who needed a blood stem cell transplant to treat cancer. Previously, two other men were apparently cured of both diseases by transplants from donors with natural resistance to HIV because they have a gene mutation that prevents HIV from entering cells.

Since donors like this are very rare, the Chinese scientists tried to create similar HIV resistance by editing that gene in blood cells in the lab to try to mimic the mutation.

The transplant put the mans cancer in remission, and the cells that were altered to resist HIV are still working 19 months later. But they comprise only 5 percent to 8 percent of such blood cells, so theyre outnumbered by ones that can still be infected.

They need to approach 90 percent or more, I think, to actually have a chance of curing HIV, June said.

Scientists are testing various ways to make the gene editing more efficient, and our results show the proof of principle for this approach, one study leader, Hongkui Deng of Peking University in Beijing, wrote in an email.

One very encouraging result: multiple tests show that the editing did not have unintended effects on other genes.

One of the concerns is that they could make a Frankenstein cell, that they would hit other genes instead of the intended target, so its good that this did not happen, June said.

China appears to be moving fast on such research and may get treatments approved sooner than the United States, June said. He has financial ties to some gene therapy companies and is leading a different study testing CRISPR to fight cancer in the U.S. Three patients have been treated so far and some results are expected by the end of this year.

Several other U.S. studies have been trying to control HIV by altering patients own blood cells using a different gene-editing tool called zinc finger nucleases. The first such test began a decade ago in the U.S.

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Gene-editing tool shows promise in fight against HIV - The Columbian

For the first time, scientists used the gene editing tool CRISPR-Cas9 in an attempt to treat an HIV patient in China. The patient showed improvements after the procedure and did not experience side effects.

The scientists at Peking University in Beijing utilized CRISPR to delete the gene called CCR5 from stem cells in a donated bone marrow. CCR5 is known for contributing to HIV infection.

A 27-year-old patient diagnosed with AIDS and acute lymphoblastic leukemia received the transplant. Doctors said the new and modified bone marrow should help treat his cancer and eliminate HIV.

"After being edited, the cells -- and the blood cells they produce -- have the ability to resist HIV infection," lead scientist Deng Hongkui told CNN.

The patient went under the knife for the bone marrow transplant in 2017. In early 2019, scientists said the man's acute lymphoblastic leukemia was in complete remission.

The stem cells with the editedCCR5 gene also stayed in his system 19 months after the procedure. The team published the results in The New England Journal of Medicine.

However, the new cells did not completely eliminatethe HIV virus. Scientists said the patient lacked enough amounts of stem cells to treat the disease.

Cells in the transplanted bone marrow carried only 5 percent to 8 percent of the edited CCR5. But it might not be a major problem for future experiments since enhancing the gene editing technique may improve outcomes, the scientists said.

"In the future, further improving the efficiency of gene-editing and optimizing the transplantation procedure should accelerate the transition to clinical applications," Deng said.

The initial study mainly aimed to test the safety and feasibility of using genetically-edited stem cells for AIDS treatment. Deng said one key finding is that the procedure did not cause any negative effect.

He added CRISPR has the potential to end blood-related diseases such as AIDS, sickle anemia, hemophilia and beta thalassemia.

Dengs team is not the first group to explore the use of CRISPR. China has been increasing its investment in the gene editing tool, which led to a number of first time experiments.

In 2016, the government announced biotechnology as part of its new Five-Year Plan. China is the first country to allow the use of CRISPR in humans and for the modification of nonviable human embryos.

CRISPR/Cas9 continues to provide scientists new ways to understand and fight previously untreatable diseases. Pixabay

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Scientists Use Gene Editing To Help HIV Patient Delete Disease In China - Medical Daily

In the quest for the next cancer cure, few researchers bother to look back at the graveyard of failed medicines to figure out what went wrong.

The number of failures is staggering: 97 percent of the time that a new drug is tested in a clinical trial for a particular type of cancer, it never makes it to the market. That means the humans (and animals) who participate in these experiments risk their lives on treatments that end up in the dustbin.

Now, a new study helps explain why the rate of failure is so high: In the case of targeted cancer therapies a relatively new class of oncology drugs the medicines may not actually hit the targets researchers intended.

Targeted therapies in cancer work differently from traditional treatments, like chemotherapy. Theyre supposed to be aimed at the specific genes, proteins, or tissues cancer cells rely on to thrive. (Chemo, on the other hand, generally works on all cells that are rapidly dividing, regardless of whether theyre healthy or cancerous.)

The new study, published in Science Translational Medicine, used CRISPR the latest and most precise gene-editing tool available to examine whether 10 different drugs worked as researchers projected. In every case, the researchers found that they didnt.

When the papers authors removed the genes from the genomes of cancer cells that were supposed to be essential for cancer growth, the cells continued to grow. And when they applied the medicines each targeting one of six genes to the newly removed genes, the drugs killed the cancer cells anyway. In other words, even when the supposed target of the therapies was fully deleted, the drugs worked.

This suggests its possible that a big driver of cancer-drug failures in clinical studies is that the drugs dont actually work as drug developers intended.

I hope this paper will help people see the need to raise to bar in terms of how we choose and validate cancer drug targets, said William George Kaelin, a Harvard University professor of medicine who was not involved in the study.

The study should also be a wake-up call for drug developers: [They] should make sure their drugs stop working if the target protein has been genetically removed, said Nathanael Gray, a Dana-Farber Cancer Institute cancer biologist, who was also independent of the research.

The finding is definitely fascinating. But so is the story of why the researchers decided to run the study in the first place and use the latest gene-editing technology to reanalyze, and possibly debunk, previous findings in cancer clinical studies.

A few years ago, one of the papers authors Jason Sheltzer, a research fellow in cancer biology at Cold Spring Harbor Laboratory and his colleagues became interested in a gene called MELK, which is supposed to serve as a biomarker for aggressive breast cancer in patients with a poor prognosis. In the US, some 270,000 new cases of invasive breast cancer will be diagnosed in 2019, and nearly 42,000 women are likely to die from the disease, according to the American Cancer Society.

The researchers started to tinker with the gene using CRISPR and found they couldnt reproduce many of the previous findings about MELK that had been uncovered using older gene-analyzing technologies, such as RNA interference. Namely, even when MELK was cut out, the breast cancer cells proliferated.

When a drug that was supposed to target MELK for breast cancer entered clinical studies, the researchers decided to use CRISPR again, this time to edit out the gene to see whether the drug still worked. We found the drug continued to kill breast cancer cells, regardless of whether the MELK it was targeting was present in the breast cancer genome, said Sheltzer.

This led Sheltzer and his colleagues to a big question: Had they just studied a uniquely bad cancer drug or did we stumble upon a bigger problem? he recalled. The extremely high failure rate [in cancer clinical trials] made us suspect there might be other instances of poorly designed drugs and poorly researched drug targets being tested in human patients.

Enter the new study. Sheltzer and his co-authors chose 10 drugs and drug targets that, like MELK, were at various stages of clinical development. They focused mainly on targets that had been discovered using RNA interference, again, a once-popular gene-analyzing technology that predated CRISPR. And they suspected that like MELK maybe itd been leading researchers down the wrong path.

In each case, they used CRISPR to cut out genes from the genomes of the cancer cells they were looking at genes thought to be essential for cancer growth. And they found that in every case, the drugs killed the cancer cells even though the gene that was supposed to be driving the cancer had been removed.

We wound up with 10 drugs that are potent anti-cancer agents. So we think that if we can figure out what these drugs actually do, we might be able to discover new cancer targets or we might be able to find patients who are more likely to respond, Sheltzer said.

Its also possible this kind of mistaken target helps explain why drugs fall short as they make their way through more and more rigorous stages of clinical studies.

But there could also be other explanations for the misfired targets. Sheltzer acknowledged that they chose medicines primarily discovered with RNA interference technology. And, Technology is always improving. So a lot of the drugs that are being tested in patients now were discovered and characterized five to 10 years ago. Its possible that targeted therapies, discovered more recently using newer genetic technologies, are more precise.

Both Kaelin and Gray shared a word of caution about the study: The researchers focused on targeted drugs that were already known to be problematic. As Kaelin put it, [They] picked drugs against targets where there was never, in my opinion, strong genetic data to support them. So, perhaps, cancer drugs with better-established targets would work as projected.

But Sheltzer says honing in on poor performers was part of the point of the study. A lot of cancer drugs get into clinical trials based on very weak genetic evidence, and when you carefully evaluate them, the rationale for targeting particular genes evaporates.

Either way, he and his colleagues hope the research inspires more analyses into why so many cancer drugs dont help patients. Research funding agencies are very interested in finding the next cure, Sheltzer argued, and they arent excited about this research into reproducibility and why some drugs fail. If we want to accelerate the quest for effective, new treatments, maybe they should be.

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Cancer treatment: drugs often fail in clinical studies. Heres a reason why. - Vox.com

Cancer Cells Resort to Cannibalism To Survive Chemo

By consuming neighboring cancer cells, some cells have found a way to obtain the energy they need to remain alive and induce relapse after a course of chemotherapy is completed.

Published in:Journal of Cell Biology

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Bone Marrow May Be the Missing Piece of the Fertility Puzzle

Study shows that when an egg is fertilized, stem cells leave the bone marrow and travel via the bloodstream to the uterus, where they help transform the uterine lining for implantation.

Published in: PLOS Biology

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Alzheimer's Risk Gene Targets the Brain's Immune Cells

The most prevalent genetic risk factor of Alzheimer's disease (AD), apolipoprotein E4, impairs the function of human brain immune cells, microglia.

Published in: Stem Cell Reports

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Researchers Use CRISPR to Correct Mutation in Duchenne Muscular Dystrophy Model

Duchenne muscular dystrophy (DMD) is a rare but devastating genetic disorder that causes muscle loss and physical impairments. Researchers at the University of Missouri School of Medicine have shown in a mouse study that the powerful gene editing technique known as CRISPR may provide the means for lifelong correction of the genetic mutation responsible for the disorder.

Published in: Molecular TherapyRead full story

Were the Neanderthals Wiped Out by a Common Childhood Illness?

The path to extinction for Neanderthals may well have been the most common and innocuous of childhood illnesses and the bane of every parent of young children chronic ear infections.

Published in:The Anatomical RecordRead full story

Failed drugs often are left on the shelf to gather dust. But sometimes, drugs can be dusted down and repurposed. In this article, we profile a new effort to bring drugs back from the dead and find solutions to conditions such as multiple sclerosis and chronic pain.

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A number of projects are underway to harness bioprinting to print functional human tissues, the first step to printing an entire organ. In this article, we take a closer look at three of these projects.

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TSE Explores Microplastics Detection Techniques

Astrocytes

Blood vessels and astrocytes in aging rat retina, confocal imaging, 40x. Blood vessels are shown in blue; astrocytes (supportive cells of the nervous system) are mostly in red. As organisms age, changes in astrocytes might contribute to disease and degeneration.

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7 Days in Science September 20, 2019 - Technology Networks

Genomes of living organism like that of humans can be edited with the technique of CRISPR. Things that could only be imagines earlier can be made possible with this technique, such as reversing congenital conditions or killing off viruses. CRISPR has now found another application in which it equips materials to change their properties when nearby there are specific DNA sequences.

The research behind this technology was done by a team of scientists from MIT and Harvard who also developed multiple types of devices using the technology. These include an electronic circuit that reacts to DNA cues, a microfluidic device with a DNA sensor that activates a valve to open and close and also gels that release drugs. The idea is to deliver therapies, perform diagnostics, and many impossible tasks up till now; by the interaction between human body and a whole set of new smart materials.

With the help of proteins known as Cas enzymes, DNA can be cut by scientists in specific locations by using CRISPR. A single- stranded DNA was used by the scientists in this new research as a structural component or a control mechanism. This gave smart biological functionality to whatever material it is in.

They developed a polyethylene glycol gel containing DNA bound to encapsulated drug. Acrylamide gel with the DNA was also created by the team. An electronic circuit with another gel was also created by the team with idea of advancing the technique where the result was conductive when the DNA strands within it are intact. One of the next things the team is working on is to find a way to use the technology to deliver engineered bacteria to help treat conditions that are gastrointestinal.

Gaurang Tayloris an MD/MBA candidate at the Johns Hopkins School of Medicine and Harvard Business School. He contributes regularly to CardioSource World News and Emergency Physicians Monthly. He is interested in developing scalable, tech-based solutions for medicine and education. He loves to share his knowledge and recent trends in the Healthcare Department by posting various articles. He has experience in medical device pathways and is passionate about understanding the human body.

Mail: gaurang.taylor@storyoffuture.com

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Biological Cues | CRISPR-Responsive Materials - Story of Future

DURHAM Biomedical engineers at Duke University have developed a method to address failures in a promising anti-cancer drug, bringing together tools from genome engineering, protein engineering and biomaterials science to improve the efficacy, accuracy and longevity of certain cancer therapies.

Using a combination of CRISPR-based targeting, a protein depot that allows for sustained release of the drug and a highly potent binding system, the team showed that their new strategy could overcome three critical problems that limit the efficacy of many cancer drugs their limited potency, their quick elimination from the body, and the ability of cancer cells to develop resistance to the drug.

The research appeared online Sept. 4 in the journal Science Advances.

More than 20 years ago, researchers discovered that the protein drug TRAIL, short for TNF-related apoptosis-inducing ligand, could effectively kill cancer cells without harming healthy cells at least, in the lab. TRAIL works by binding to specific protein receptors on cancer cells, ominously called death receptors, sending a signal that causes the cells to self-destruct. Although initial experiments showed the drug worked in a variety of cancer cell lines, including melanoma, lymphoma, pancreatic, prostate, lung, colon and breast cancer, TRAIL and similar drugs surprised researchers by showing limited success in clinical trials.

After more study, scientists pinpointed three reasons why the promising drug failed: TRAIL wasnt potent enough, the drug was being cleared from the body too quickly and some cancer cells were resistant to the therapy.

Duke engineers improve CRISPR genome editing with biomedical tails

Using a combination of three tools a highly potent protein drug, a depot that allows for sustained release of the drug, and CRISPR/Cas9 based gene editing to pinpoint the cause of resistance to the drug the Duke team, which included Mandana Manzari, a recent PhD graduate,Ashutosh Chilkoti, the chair of Duke biomedical engineering, andKris Wood, an assistant professor of pharmacology and cancer biology, demonstrated that their new strategy could provide a solution to these problems and give protein-based anti-cancer biologics like TRAIL that failed in the clinic a second chance.

The real significance of this research for me is the true cross-disciplinary nature of it, said Manzari, first author on the paper and now a post-doctoral researcher at the Memorial Sloan Kettering Cancer Center in New York. This is really the first example Ive seen where were bringing in pharmacology, drug delivery, and genomics to pinpoint the exact circumstances that cause a biologic to fail and then develop solutions.

The first step of the process involved addressing TRAILs limited potency. Typically, cells have multiple death receptors, but a specific receptor called death receptor 5 (DR5) is more prevalent in certain cancer cells. TRAIL, a three-part protein, binds to DR5 and links three death receptors together, sending a signal for cells to self-destruct. TRAIL can also bind to other death receptors and decoy receptors on normal cells. A more potent drug would be specific for a given death receptor, like DR5 that is present on cancer cells, and link together larger numbers of the receptor on a cell surface to send a stronger death signal to the cancer cell.

Manzari produced a highly potent, six-part death receptor agonist (DRA) that could bind six death receptors together and indude a much stronger self-destruct signal.

Next, the team examined how to prevent the super-potent death receptor agonist from being cleared from the body too quickly. They genetically fused the DRA to a temperature-responsive protein called elastin-like polypeptide (ELP), which forms a gel-like depot within a room-temperature solution. After the solution is injected under the skin, it dissolves, releasing the DRA over a longer period of time.

Duke researchers: Single CRISPR treatment provides long-term benefits in mice

Finally, Chilkoti and Manzari partnered with Kris Wood to better understand what caused certain cells to resist death by TRAIL or death receptor agonist (DRA). The team systematically disabled various genes in the cancer cells using CRISPR/Cas9 until they could deduce which were responsible for TRAIL or DRA resistance. Then they selected drugs to target the proteins produced by those genes and paired them with the DRA slow-release depot.

This work opens another exciting avenue for targeting a critical cell death pathway in cancer, an area of increasing interest in the translational cancer therapeutics community, Wood said.

When we figured out the genes that drive resistance, we were able to map them to commercially-available drugs that could specifically target the proteins that come from those genes, said Manzari. It basically gave us a platform to figure out what drugs we can combine with the DRA in cases where this drug or other protein drugs dont work well to nip that resistance in the bud.

With their triple-whammy tool, the team was able to effectively overcome intrinsic resistance, repress tumor growth and extend survival in mice that were implanted with colorectal cancers from human patients that are highly resistant to treatment with TRAIL.

Now, the researchers are considering how they could apply this method to other protein and small-molecule drugs that face similar barriers that limit their effectiveness.

I think the thing that really sets this approach apart is designing each piece of the platform rationally to address a specific problem and bringing them all together holistically to solve three critical problems that limit not just TRAIL, but many new cancer therapies, Chilkoti said.

Typically the protein engineering is one platform, the ELP strategy is one platform and the genomic screen strategy is its own platform, Manzari said. This is a good example of true synergy of engineering, pharmacology, genomics and materials. People always talk about bringing those together, and this is a clear example of that.

(C) Duke University

This research was funded by the National Institutes of Health (5R01EB007025-08, 5R01EB000188-12, 5R01GM061232-16, R01CA207083, and 5T32GM007105) and the Duke University BME/DCI Collaborative Grant.

CITATION: Genomically Informed Small Molecule Drugs Overcome Resistance to a Sustained Release Formulation of an Engineered Death Receptor Agonist in Patient-Derived Tumor Models, Mandana T. Manzari, Grace R. Anderson, Kevin H. Lin, Ryan S. Soderquist, Merve Cakir, Mitchell Zhang, Chandler E. Moore, Rachel N. Skelton, Mareva Fevre, Xinghai Li, Joseph J. Bellucci, Suzanne E. Wardell, Simone A. Costa, Kris C. Wood, Ashutosh Chilkoti. Science Advances, 2019. DOI 10.1126/sciadv.aaw9162

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Duke researchers utilize gene editing to improve cancer drugs' performance - WRAL Tech Wire

(more about Power Words)

applicationA particular use or function of something.

base (in genetics) A shortened version of the term nucleobase. These bases are building blocks of DNA and RNA molecules.

biologyThe study of living things. The scientists who study them are known as biologists.

Cas9An enzyme that geneticists are now using to help edit genes. It can cut through DNA, allowing it to fix broken genes, splice in new ones or disable certain genes. Cas9 is shepherded to the place it is supposed to make cuts by CRISPRs, a type of genetic guides. The Cas9 enzyme came from bacteria. When viruses invade a bacterium, this enzyme can chop up the germs DNA, making it harmless.

cellThe smallest structural and functional unit of an organism. Typically too small to see with the naked eye, it consists of watery fluid surrounded by a membrane or wall. Animals are made of anywhere from thousands to trillions of cells, depending on their size. Some organisms, such as yeasts, molds, bacteria and some algae, are composed of only one cell.

chemicalA substance formed from two or more atoms that unite (become bonded together) in a fixed proportion and structure. For example, water is a chemical made of two hydrogen atoms bonded to one oxygen atom. Its chemical symbol is H2O.

CRISPRAn abbreviation pronounced crisper for the term clustered regularly interspaced short palindromic repeats. These are pieces of RNA, an information-carrying molecule. They are copied from the genetic material of viruses that infect bacteria. When a bacterium encounters a virus that it was previously exposed to, it produces an RNA copy of the CRISPR that contains that virus genetic information. The RNA then guides an enzyme, called Cas9, to cut up the virus and make it harmless. Scientists are now building their own versions of CRISPR RNAs. These lab-made RNAs guide the enzyme to cut specific genes in other organisms. Scientists use them, like a genetic scissors, to edit or alter specific genes so that they can then study how the gene works, repair damage to broken genes, insert new genes or disable harmful ones.

developmental(in biology) An adjective that refers to the changes an organism undergoes from conception through adulthood. Those changes often involve chemistry, size and sometimes even shape.

DNA(short for deoxyribonucleic acid) A long, double-stranded and spiral-shaped molecule inside most living cells that carries genetic instructions. It is built on a backbone of phosphorus, oxygen, and carbon atoms. In all living things, from plants and animals to microbes, these instructions tell cells which molecules to make.

engineeringThe field of research that uses math and science to solve practical problems.

fieldAn area of study, as in: Her field of research was biology. Also a term to describe a real-world environment in which some research is conducted, such as at sea, in a forest, on a mountaintop or on a city street. It is the opposite of an artificial setting, such as a research laboratory.

fluorescentCapable of absorbing and reemitting light. That reemitted light is known as a fluorescence.

gene(adj. genetic) A segment of DNA that codes, or holds instructions, for producing a protein. Offspring inherit genes from their parents. Genes influence how an organism looks and behaves.

genomeThe complete set of genes or genetic material in a cell or an organism. The study of this genetic inheritance housed within cells is known as genomics.

muscleA type of tissue used to produce movement by contracting its cells, known as muscle fibers. Muscle is rich in a protein, which is why predatory species seek prey containing lots of this tissue.

mutation(v. mutate) Some change that occurs to a gene in an organisms DNA. Some mutations occur naturally. Others can be triggered by outside factors, such as pollution, radiation, medicines or something in the diet. A gene with this change is referred to as a mutant.

nucleusPlural is nuclei. (in biology) A dense structure present in many cells. Typically a single rounded structure encased within a membrane, the nucleus contains the genetic information.

organ(in biology) Various parts of an organism that perform one or more particular functions. For instance, an ovary is an organ that makes eggs, the brain is an organ that interprets nerve signals and a plants roots are organs that take in nutrients and moisture.

palindrome (adj. palindromic) A word, a name or a phrase that has the same ordering of letters when read forwards or backwards. For instance, dad and mom are both palindromes.

proteinCompoundmade from one or more long chains of amino acids. Proteins are an essential part of all living organisms. They form the basis of living cells, muscle and tissues; they also do the work inside of cells. The hemoglobin in blood and the antibodies that attempt to fight infections are among the better-known, stand-alone proteins. Medicines frequently work by latching onto proteins.

RNAA molecule that helps read the genetic information contained in DNA. A cells molecular machinery reads DNA to create RNA, and then reads RNA to create proteins.

tag(in biology) To attach some rugged band or package of instruments onto an animal. Sometimes the tag is used to give each individual a unique identification number. Once attached to the leg, ear or other part of the body of a critter, it can effectively become the animals name. In some instances, a tag can collect information from the environment around the animal as well. This helps scientists understand both the environment and the animals role within it.

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Explainer: How CRISPR works | Science News for Students

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Tourrire, H. et al. The RasGAP-associated endoribonuclease G3BP assembles stress granules. J. Cell Biol. 160, 823831 (2003).

Tafer, H. et al. The impact of target site accessibility on the design of effective siRNAs. Nat. Biotechnol. 26, 578583 (2008)

Mann, D. G. et al. Gateway-compatible vectors for high-throughput gene functional analysis in switchgrass (Panicum virgatum L.) and other monocot species. Plant Biotechnol. J. 10, 226236 (2012)

Zhang, Y. et al. A highly efficient rice green tissue protoplast system for transient gene expression and studying light/chloroplast-related processes. Plant Methods 7, 30 (2011)

Joung, J. et al. Genome-scale CRISPRCas9 knockout and transcriptional activation screening. Nat. Protocols 12, 828863 (2017)

Jain, M., Nijhawan, A., Tyagi, A. K. & Khurana, J. P. Validation of housekeeping genes as internal control for studying gene expression in rice by quantitative real-time PCR. Biochem. Biophys. Res. Commun. 345, 646651 (2006)

Bernhart, S. H., Hofacker, I. L. & Stadler, P. F. Local RNA base pairing probabilities in large sequences. Bioinformatics 22, 614615 (2006)

Li, B. & Dewey, C. N. RSEM: accurate transcript quantification from RNA-Seq data with or without a reference genome. BMC Bioinformatics 12, 323 (2011)

Schindelin, J. et al. Fiji: an open-source platform for biological-image analysis. Nat. Methods 9, 676682 (2012)

Read more:
RNA targeting with CRISPRCas13 | Nature

Discovery of CRISPR and its function 1993 - 2005 Francisco Mojica, University of Alicante, Spain

Francisco Mojica was the first researcher to characterize what is now called a CRISPR locus, reported in 1993. He worked on them throughout the 1990s, and in 2000, he recognized that what had been reported as disparate repeat sequences actually shared a common set of features, now known to be hallmarks of CRISPR sequences (he coined the term CRISPR through correspondence with Ruud Jansen, who first used the term in print in 2002). In 2005 he reported that these sequences matched snippets from the genomes of bacteriophage (Mojica et al., 2005). This finding led him to hypothesize, correctly, that CRISPR is an adaptive immune system. Another group, working independently, published similar findings around this same time (Pourcel et al., 2005)

Discovery of Cas9 and PAMMay, 2005 Alexander Bolotin, French National Institute for Agricultural Research (INRA)

Bolotin was studying the bacteria Streptococcus thermophilus, which had just been sequenced, revealing an unusual CRISPR locus (Bolotin et al., 2005). Although the CRISPR array was similar to previously reported systems, it lacked some of the known cas genes and instead contained novel cas genes, including one encoding a large protein they predicted to have nuclease activity, which is now known as Cas9. Furthermore, they noted that the spacers, which have homology to viral genes, all share a common sequence at one end. This sequence, the protospacer adjacent motif (PAM), is required for target recognition.

Hypothetical scheme of adaptive immunityMarch, 2006 Eugene Koonin, US National Center for Biotechnology Information, NIH

Koonin was studying clusters of orthologous groups of proteins by computational analysis and proposed a hypothetical scheme for CRISPR cascades as bacterial immune system based on inserts homologous to phage DNA in the natural spacer array, abandoning previous hypothesis that the Cas proteins might comprise a novel DNA repair system.(Makarova et al., 2006)

Experimental demonstration of adaptive immunityMarch, 2007 Philippe Horvath, Danisco France SAS

S. thermophilus is widely used in the dairy industry to make yogurt and cheese, and scientists at Danisco wanted to explore how it responds to phage attack, a common problem in industrial yogurt making. Horvath and colleagues showed experimentally that CRISPR systems are indeed an adaptive immune system: they integrate new phage DNA into the CRISPR array, which allows them to fight off the next wave of attacking phage (Barrangou et al., 2007). Furthermore, they showed that Cas9 is likely the only protein required for interference, the process by which the CRISPR system inactivates invading phage, details of which were not yet known.

Spacer sequences are transcribed into guide RNAsAugust, 2008 John van der Oost, University of Wageningen, Netherlands

Scientists soon began to fill in some of the details on exactly how CRISPR-Cas systems interfere with invading phage. The first piece of critical information came from John van der Oost and colleagues who showed that in E-scherichia coli, spacer sequences, which are derived from phage, are transcribed into small RNAs, termed CRISPR RNAs (crRNAs), that guide Cas proteins to the target DNA (Brouns et al., 2008).

CRISPR acts on DNA targets December, 2008 Luciano Marraffini and Erik Sontheimer, Northwestern University, Illinois

The next key piece in understanding the mechanism of interference came from Marraffini and Sontheimer, who elegantly demonstrated that the target molecule is DNA, not RNA (Marraffini and Sontheimer, 2008). This was somewhat surprising, as many people had considered CRISPR to be a parallel to eukaryotic RNAi silencing mechanisms, which target RNA. Marraffini and Sontheimer explicitly noted in their paper that this system could be a powerful tool if it could be transferred to non-bacterial systems. (It should be noted, however, that a different type of CRISPR system can target RNA (Hale et al., 2009)).

Cas9 cleaves target DNADecember, 2010 Sylvain Moineau, University of Laval, Quebec City, Canada

Moineau and colleagues demonstrated that CRISPR-Cas9 creates double-stranded breaks in target DNA at precise positions, 3 nucleotides upstream of the PAM (Garneau et al., 2010). They also confirmed that Cas9 is the only protein required for cleavage in the CRISPR-Cas9 system. This is a distinguishing feature of Type II CRISPR systems, in which interference is mediated by a single large protein (here Cas9) in conjunction with crRNAs.

Discovery of tracrRNA for Cas9 systemMarch, 2011 Emmanuelle Charpentier, Umea University, Sweden and University of Vienna, Austria

The final piece to the puzzle in the mechanism of natural CRISPR-Cas9-guided interference came from the group of Emmanuelle Charpentier. They performed small RNA sequencing on Streptococcus pyogenes, which has a Cas9-containing CRISPR-Cas system. They discovered that in addition to the crRNA, a second small RNA exists, which they called trans-activating CRISPR RNA (tracrRNA) (Deltcheva et al., 2011). They showed that tracrRNA forms a duplex with crRNA, and that it is this duplex that guides Cas9 to its targets.

CRISPR systems can function heterologously in other species July, 2011 Virginijus Siksnys, Vilnius University, Lithuania

Siksnys and colleagues cloned the entire CRISPR-Cas locus from S. thermophilus (a Type II system) and expressed it in E. coli (which does not contain a Type II system), where they demonstrated that it was capable of providing plasmid resistance (Sapranauskas et al., 2011). This suggested that CRISPR systems are self-contained units and verified that all of the required components of the Type II system were known.

Biochemical characterization of Cas9-mediated cleavageSeptember, 2012 Virginijus Siksnys, Vilnius University, Lithuania

Taking advantage of their heterologous system, Siksnys and his team purified Cas9 in complex with crRNA from the E. coli strain engineered to carry the S. thermophilus CRISPR locus and undertook a series of biochemical experiments to mechanistically characterize Cas9s mode of action (Gasiunas et al., 2012).They verified the cleavage site and the requirement for the PAM, and using point mutations, they showed that the RuvC domain cleaves the non-complementary strand while the HNH domain cleaves the complementary site. They also noted that the crRNA could be trimmed down to a 20-nt stretch sufficient for efficient cleavage. Most impressively, they showed that they could reprogram Cas9 to target a site of their choosing by changing the sequence of the crRNA.

June, 2012 Charpentier and Jennifer Doudna, University of California, Berkeley

Similar findings as those in Gasiunas et al. were reported at almost the same time by Emmanuelle Charpentier in collaboration with Jennifer Doudna at the University of California, Berkeley (Jinek et al., 2012). Charpentier and Doudna also reported that the crRNA and the tracrRNA could be fused together to create a single, synthetic guide, further simplifying the system. (Although published in June 2012, this paper was submitted after Gasiunas et al.)

CRISPR-Cas9 harnessed for genome editingJanuary, 2013 Feng Zhang, Broad Institute of MIT and Harvard, McGovern Institute for Brain Research at MIT, Massachusetts

Zhang, who had previously worked on other genome editing systems such as TALENs, was first to successfully adapt CRISPR-Cas9 for genome editing in eukaryotic cells (Cong et al., 2013). Zhang and his team engineered two different Cas9 orthologs (from S. thermophilus and S. pyogenes) and demonstrated targeted genome cleavage in human and mouse cells. They also showed that the system (i) could be programmed to target multiple genomic loci, and (ii) could drive homology-directed repair. Researchers from George Churchs lab at Harvard University reported similar findings in the same issue of Science (Mali et al., 2013).

Citations

Barrangou, R., Fremaux, C., Deveau, H., Richards, M., Boyaval, P., Moineau, S., Romero, D.A., and Horvath, P. (2007). CRISPR provides acquired resistance against viruses in prokaryotes. Science 315, 17091712.

Bolotin, A., Quinquis, B., Sorokin, A.,and Ehrlich, S.D. (2005). Clustered regularly interspaced short palindrome repeats (CRISPRs) have spacers of extrachromosomal origin. Microbiology 151, 25512561.

Brouns, S.J., Jore, M.M., Lundgren, M., Westra, E.R., Slijkhuis, R.J., Snijders, A.P., Dickman, M.J., Makarova, K.S., Koonin, E.V., van der Oost, J. (2008) Small CRISPR RNAs guide antiviral defense in prokaryotes. Science 321, 960-964.

Cong, L., Ran, F.A., Cox, D., Lin, S., Barretto, R., Habib, N., Hsu, P.D., Wu, X., Jiang, W., Marraffini, L.A., et al. (2013). Multiplex genome engineering using CRISPR/Cas systems. Science 339, 819823.

Deltcheva, E., Chylinski, K., Sharma, C.M., Gonzales, K., Chao, Y., Pirzada, Z.A., Eckert, M.R., Vogel, J., and Charpentier, E. (2011). CRISPR RNA maturation by trans-encoded small RNA and host factor RNase III. Nature 471, 602607.

Gasiunas, G., Barrangou, R., Horvath, P., and Siksnys, V. (2012). Cas9crRNA ribonucleoprotein complex mediates specific DNA cleavage for adaptive immunity in bacteria. Pnas 109, E2579E2586.

Hale, C.R., Zhao, P., Olson, S., Duff, M.O., Graveley, B.R., Wells, L., Terns, R.M., and Terns, M.P. (2009). RNA-Guided RNA Cleavage by a CRISPR RNA-Cas Protein Complex. Cell 139, 945956.

Jinek, M., Chylinski, K., Fonfara, I., Hauer, M., Doudna, J.A., and Charpentier, E. (2012). A programmable dual-RNA-guided DNA endonuclease in adaptive bacterial immunity. Science 337, 816821.

Makarova, K.S., Grishin, N.V., Shabalina, S.A., Wolf, Y.I., Koonin, E.V. (2006). A putative RNA-interference-based immune system in prokaryotes: computational analysis of the predicted enzymatic machinery, functional analogies with eukaryotic RNAi, and hypothetical mechanisms of action. Biology Direct 2006, 1:7.

Mali, P., Yang, L., Esvelt, K.M., Aach, J., Guell, M., DiCarlo, J.E., Norville, J.E., and Church, G.M. (2013). RNA-guided human genome engineering via Cas9. Science 339, 823826.

Marraffini, L.A., and Sontheimer, E.J. (2008). CRISPR interference limits horizontal gene transfer in staphylococci by targeting DNA. Science 322, 18431845.

Mojica, F.J.M., D ez-Villase or, C.S., Garc a-Mart nez, J.S., and Soria, E. (2005). Intervening Sequences of Regularly Spaced Prokaryotic Repeats Derive from Foreign Genetic Elements. J Mol Evol 60, 174182.

Pourcel, C., Salvignol, G., and Vergnaud, G. (2005). CRISPR elements in Yersinia pestis acquire new repeats by preferential uptake of bacteriophage DNA, and provide additional tools for evolutionary studies. Microbiology 151, 653663.

Sapranauskas, R., Gasiunas, G., Fremaux, C., Barrangou, R., Horvath, P., and Siksnys, V. (2011). The Streptococcus thermophilus CRISPR/Cas system provides immunity in Escherichia coli. Nucl. Acids Res. 39, gkr606gkr9282.

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CRISPR Timeline | Broad Institute

-Enrollment ongoing in Phase 1/2 clinical trials of CTX001 for patients with severe hemoglobinopathies-

-IND and CTA approved for CTX110, wholly-owned allogeneic CAR-T cell therapy targeting CD19+ malignancies-

-On track to initiate Phase 1/2 clinical trial for CTX110 in 1H 2019-

-$437.5 million in cash as of March 31, 2019-

ZUG, Switzerland and CAMBRIDGE, Mass., April 29, 2019 (GLOBE NEWSWIRE) -- CRISPR Therapeutics(CRSP), a biopharmaceutical company focused on creating transformative gene-based medicines for serious diseases, today reported financial results for the first quarter ended March 31, 2019.

This past quarter, we began an important new period for CRISPR Therapeutics with the treatment of the first patient in our clinical trial for CTX001 in hemoglobinopathies, said Samarth Kulkarni, Ph.D., Chief Executive Officer of CRISPR Therapeutics. This is a significant landmark for the Company and we continue to enroll patients in our trials for both beta thalassemia and sickle cell disease. With the acceptance of our IND and CTA for CTX110, we look forward to the initiation of our clinical trials for our allogeneic CAR-T programs in the near-term and hope to bring other CAR-T programs to the clinic in the next six to twelve months.

Recent Highlights and Outlook

First Quarter 2019 Financial Results

About CRISPR TherapeuticsCRISPR Therapeutics is a leading gene editing company focused on developing transformative gene-based medicines for serious diseases using its proprietary CRISPR/Cas9 platform. CRISPR/Cas9 is a revolutionary gene editing technology that allows for precise, directed changes to genomic DNA. CRISPR Therapeutics has established a portfolio of therapeutic programs across a broad range of disease areas including hemoglobinopathies, oncology, regenerative medicine and rare diseases. To accelerate and expand its efforts, CRISPR Therapeutics has established strategic collaborations with leading companies including Bayer AG, Vertex Pharmaceuticals and ViaCyte, Inc. CRISPR Therapeutics AG is headquartered in Zug, Switzerland, with its wholly-owned U.S. subsidiary, CRISPR Therapeutics, Inc., and R&D operations based in Cambridge, Massachusetts, and business offices in London, United Kingdom. For more information, please visit http://www.crisprtx.com.

CRISPR Forward-Looking StatementThis press release may contain a number of forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, as amended, including statements regarding CRISPR Therapeutics expectations about any or all of the following: (i) clinical trials (including, without limitation, the timing of filing of clinical trial applications and INDs, any approvals thereof and the timing of commencement of clinical trials), development timelines and discussions with regulatory authorities related to product candidates under development by CRISPR Therapeutics and its collaborators; (ii) the number of patients that will be evaluated, the anticipated date by which enrollment will be completed and the data that will be generated by ongoing and planned clinical trials, and the ability to use that data for the design and initiation of further clinical trials; (iii) the scope and timing of ongoing and potential future clinical trials; (iv) the intellectual property coverage and positions of CRISPR Therapeutics, its licensors and third parties; (v) the sufficiency of CRISPR Therapeutics cash resources; and (vi) the therapeutic value, development, and commercial potential of CRISPR/Cas9 gene editing technologies and therapies. Without limiting the foregoing, the words believes, anticipates, plans, expects and similar expressions are intended to identify forward-looking statements. You are cautioned that forward-looking statements are inherently uncertain. Although CRISPR Therapeutics believes that such statements are based on reasonable assumptions within the bounds of its knowledge of its business and operations, forward-looking statements are neither promises nor guarantees and they are necessarily subject to a high degree of uncertainty and risk. Actual performance and results may differ materially from those projected or suggested in the forward-looking statements due to various risks and uncertainties. These risks and uncertainties include, among others: the outcomes for each CRISPR Therapeutics planned clinical trials and studies may not be favorable; that one or more of CRISPR Therapeutics internal or external product candidate programs will not proceed as planned for technical, scientific or commercial reasons; that future competitive or other market factors may adversely affect the commercial potential for CRISPR Therapeutics product candidates; uncertainties inherent in the initiation and completion of preclinical studies for CRISPR Therapeutics product candidates; availability and timing of results from preclinical studies; whether results from a preclinical trial will be predictive of future results of the future trials; uncertainties about regulatory approvals to conduct trials or to market products; uncertainties regarding the intellectual property protection for CRISPR Therapeutics technology and intellectual property belonging to third parties; and those risks and uncertainties described under the heading "Risk Factors" in CRISPR Therapeutics most recent annual report on Form 10-K, and in any other subsequent filings made by CRISPR Therapeutics with the U.S. Securities and Exchange Commission, which are available on the SEC's website at http://www.sec.gov. Existing and prospective investors are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date they are made. CRISPR Therapeutics disclaims any obligation or undertaking to update or revise any forward-looking statements contained in this press release, other than to the extent required by law.

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CRISPR Therapeutics AGCondensed Consolidated Balance Sheets Data(Unaudited, in thousands)

Investor Contact:Susan Kimsusan.kim@crisprtx.com

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Gene editing method

CRISPR gene editing is a method by which the genomes of living organisms may be edited. It is based on a simplified version of the bacterial CRISPR/Cas (CRISPR-Cas9) antiviral defense system. By delivering the Cas9 nuclease complexed with a synthetic guide RNA (gRNA) into a cell, the cell's genome can be cut at a desired location, allowing existing genes to be removed and/or new ones added.[1] The Cas9-gRNA complex corresponds with the CAS III CRISPR-RNA complex in the accompanying diagram.

While genomic editing in eukaryotic cells has been possible using various methods since the 1980s, the methods employed had proved to be inefficient and impractical to implement on a larger scale. Genomic editing leads to irreversible changes to the gene. Working like genetic scissors, the Cas9 nuclease opens both strands of the targeted sequence of DNA to introduce the modification by one of two methods. Knock-in mutations, facilitated via Homology Directed Repair (HDR), is the traditional pathway of targeted genomic editing approaches.[2] This allows for the introduction of targeted DNA damage and repair. HDR employs the use of similar DNA sequences to drive the repair of the break via the incorporation of exogenous DNA to function as the repair template.[2] This method relies on the periodic and isolated occurrence of DNA damage at the target site in order for a repair to commence. Knock-out mutations caused by Cas9/CRISPR results in the repair of the double-strand break by means of NHEJ (Non-Homologous End Joining). NHEJ can often result in random deletions or insertions at the repair site disrupting or altering gene functionality. Therefore, genomic engineering by CRISPR-Cas9 allows researchers the ability to generate targeted random gene disruption.

Because of this, the precision of genomic editing is a great concern. With the discovery of CRISPR and specifically the Cas9 nuclease molecule, efficient and highly selective editing is now a reality. Cas9 allows for a reliable method of creating a targeted break at a specific location as designated by the crRNA and tracrRna guide strands.[3] Cas9 derived from Streptococcus pyogenes bacteria has facilitated the targeted genomic modification in eukaryotic cells. The ease with which researchers can insert Cas9 and template RNA in order to silence or cause point mutations on specific loci has proved invaluable to the quick and efficient mapping of genomic models and biological processes associated with various genes in a variety of eukaryotes. A newly engineered variant of the Cas9 nuclease has been developed that significantly reduces off-target manipulation. Called spCas9-HF1 (Streptococcus pyogenes Cas9 High Fidelity 1), it has a success rate of modification in vivo of 85% and undetectable off-target manipulations as measured by genome wide break capture and targeted sequencing methods used to measure total genomic changes.[4][5]

CRISPR-Cas genome editing techniques have many potential applications, including medicine and crop seed enhancement. The use of CRISPR-Cas9-gRNA complex for genome editing[6] was the AAAS's choice for breakthrough of the year in 2015.[7] Bioethical concerns have been raised about the prospect of using CRISPR for germline editing.[8]

In the early 2000s, researchers developed zinc finger nucleases (ZFNs), synthetic proteins whose DNA-binding domains enable them to create double-stranded breaks in DNA at specific points. In 2010, synthetic nucleases called transcription activator-like effector nucleases (TALENs) provided an easier way to target a double-stranded break to a specific location on the DNA strand. Both zinc finger nucleases and TALENs require the creation of a custom protein for each targeted DNA sequence, which is a more difficult and time-consuming process than that for guide RNAs. CRISPRs are much easier to design because the process requires making only a short RNA sequence.[9]

Whereas RNA interference (RNAi) does not fully suppress gene function, CRISPR, ZFNs and TALENs provide full irreversible gene knockout.[10] CRISPR can also target several DNA sites simultaneously by simply introducing different gRNAs. In addition, CRISPR costs are relatively low.[10][11][12]

CRISPR-Cas9 genome editing is carried out with a Type II CRISPR system. When utilized for genome editing, this system includes Cas9, crRNA, tracrRNA along with an optional section of DNA repair template that is utilized in either non-homologous end joining (NHEJ) or homology directed repair (HDR).

CRISPR-Cas9 often employs a plasmid to transfect the target cells.[13] The main components of this plasmid are displayed in the image and listed in the table. The crRNA needs to be designed for each application as this is the sequence that Cas9 uses to identify and directly bind to the cell's DNA. The crRNA must bind only where editing is desired. The repair template is designed for each application, as it must overlap with the sequences on either side of the cut and code for the insertion sequence.

Multiple crRNAs and the tracrRNA can be packaged together to form a single-guide RNA (sgRNA).[14] This sgRNA can be joined together with the Cas9 gene and made into a plasmid in order to be transfected into cells.

CRISPR-Cas9 offers a high degree of fidelity and relatively simple construction. It depends on two factors for its specificity: the target sequence and the PAM. The target sequence is 20 bases long as part of each CRISPR locus in the crRNA array.[13] A typical crRNA array has multiple unique target sequences. Cas9 proteins select the correct location on the host's genome by utilizing the sequence to bond with base pairs on the host DNA. The sequence is not part of the Cas9 protein and as a result is customizable and can be independently synthesized.[15][16]

The PAM sequence on the host genome is recognized by Cas9. Cas9 cannot be easily modified to recognize a different PAM sequence. However this is not too limiting as it is a short sequence and nonspecific (e.g. the SpCas9 PAM sequence is 5'-NGG-3' and in the human genome occurs roughly every 8 to 12 base pairs).[13]

Once these have been assembled into a plasmid and transfected into cells the Cas9 protein with the help of the crRNA finds the correct sequence in the host cell's DNA and depending on the Cas9 variant creates a single or double strand break in the DNA.[17]

Properly spaced single strand breaks in the host DNA can trigger homology directed repair, which is less error prone than the non-homologous end joining that typically follows a double strand break. Providing a DNA repair template allows for the insertion of a specific DNA sequence at an exact location within the genome. The repair template should extend 40 to 90 base pairs beyond the Cas9 induced DNA break.[13] The goal is for the cell's HDR process to utilize the provided repair template and thereby incorporate the new sequence into the genome. Once incorporated, this new sequence is now part of the cell's genetic material and passes into its daughter cells.

Many online tools are available to aid in designing effective sgRNA sequences.[18][19]

Delivery of Cas9, sgRNA, and associated complexes into cells can occur via viral and non-viral systems. Electroporation of DNA, RNA, or ribonucleocomplexes is a common technique, though it can result in harmful effects on the target cells.[20] Chemical transfection techniques utilizing lipids have also been used to introduce sgRNA in complex with Cas9 into cells.[21] Hard-to-transfect cells (e.g. stem cells, neurons, and hematopoietic cells) require more efficient delivery systems such as those based on lentivirus (LVs), adenovirus (AdV) and adeno-associated virus (AAV).[22][23]

Several variants of CRISPR-Cas9 allow gene activation or genome editing with an external trigger such as light or small molecules.[24][25][26] These include photoactivatable CRISPR systems developed by fusing light-responsive protein partners with an activator domain and a dCas9 for gene activation,[27][28] or fusing similar light responsive domains with two constructs of split-Cas9,[29][30] or by incorporating caged unnatural amino acids into Cas9,[31] or by modifying the guide RNAs with photocleavable complements for genome editing.[32]

Methods to control genome editing with small molecules include an allosteric Cas9, with no detectable background editing, that will activate binding and cleavage upon the addition of 4-hydroxytamoxifen (4-HT),[24] 4-HT responsive intein-linked Cas9s[33] or a Cas9 that is 4-HT responsive when fused to four ERT2 domains.[34] Intein-inducible split-Cas9 allows dimerization of Cas9 fragments[35] and Rapamycin-inducible split-Cas9 system developed by fusing two constructs of split Cas9 with FRB and FKBP fragments.[36] Furthermore, other studies have shown to induce transcription of Cas9 with a small molecule, doxycycline.[37][38] Small molecules can also be used to improve Homology Directed Repair (HDR),[39] often by inhibiting the Non-Homologous End Joining (NHEJ) pathway.[40] These systems allow conditional control of CRISPR activity for improved precision, efficiency and spatiotemporal control.

Cas9 genomic modification has allowed for the quick and efficient generation of transgenic models within the field of genetics. Cas9 can be easily introduced into the target cells via plasmid transfection along with sgRNA in order to model the spread of diseases and the cell's response and defense to infection.[41] The ability of Cas9 to be introduced in vivo allows for the creation of more accurate models of gene function, mutation effects, all while avoiding the off-target mutations typically observed with older methods of genetic engineering. The CRISPR and Cas9 revolution in genomic modeling doesn't only extend to mammals. Traditional genomic models such as Drosophila melanogaster, one of the first model species, have seen further refinement in their resolution with the use of Cas9.[41] Cas9 uses cell-specific promoters allowing a controlled use of the Cas9. Cas9 is an accurate method of treating diseases due to the targeting of the Cas9 enzyme only affecting certain cell types. The cells undergoing the Cas9 therapy can also be removed and reintroduced to provide amplified effects of the therapy.[42]

CRISPR-Cas9 can be used to edit the DNA of organisms in vivo and entire chromosomes can be eliminated from an organism at any point in its development. Chromosomes that have been deleted in vivo are the Y chromosomes and X chromosomes of adult lab mice and human chromosomes 14 and 21, in embryonic stem cell lines and aneuploid mice respectively. This method might be useful for treating genetic aneuploid diseases such as Down Syndrome and intersex disorders.[43]

Successful in vivo genome editing using CRISPR-Cas9 has been shown in several model organisms, such as Escherichia coli,[44] Saccharomyces cerevisiae,[45] Candida albicans,[46] Caenorhadbitis elegans,[47] Arabidopsis,[48] Danio rerio,[49] Mus musculus.[50][51] Successes have been achieved in the study of basic biology, in the creation of disease models,[47] and in the experimental treatment of disease models.[52]

Concerns have been raised that off-target effects (editing of genes besides the ones intended) may obscure the results of a CRISPR gene editing experiment (the observed phenotypic change may not be due to modifying the target gene, but some other gene). Modifications to CRISPR have been made to minimize the possibility of off-target effects. In addition, orthogonal CRISPR experiments are recommended to confirm the results of a gene editing experiment.[53][54]

CRISPR simplifies creation of animals for research that mimic disease or show what happens when a gene is knocked down or mutated. CRISPR may be used at the germline level to create animals where the gene is changed everywhere, or it may be targeted at non-germline cells.[55][56][57]

CRISPR can be utilized to create human cellular models of disease. For instance, applied to human pluripotent stem cells CRISPR introduced targeted mutations in genes relevant to polycystic kidney disease (PKD) and focal segmental glomerulosclerosis (FSGS).[58] These CRISPR-modified pluripotent stem cells were subsequently grown into human kidney organoids that exhibited disease-specific phenotypes. Kidney organoids from stem cells with PKD mutations formed large, translucent cyst structures from kidney tubules. The cysts were capable of reaching macroscopic dimensions, up to one centimeter in diameter.[59] Kidney organoids with mutations in a gene linked to FSGS developed junctional defects between podocytes, the filtering cells affected in that disease. This was traced to the inability of podocytes ability to form microvilli between adjacent cells.[60] Importantly, these disease phenotypes were absent in control organoids of identical genetic background, but lacking the CRISPR modifications.[58]

A similar approach was taken to model long QT syndrome in cardiomyocytes derived from pluripotent stem cells.[61] These CRISPR-generated cellular models, with isogenic controls, provide a new way to study human disease and test drugs.

CRISPR-Cas technology has been proposed as a treatment for multiple human diseases, especially those with a genetic cause.[62] Its ability to modify specific DNA sequences makes it a tool with potential to fix disease-causing mutations. Early research in animal models suggest that therapies based on CRISPR technology have potential to treat a wide range of diseases,[63] including cancer,[64] beta-thalassemia,[65] sickle cell disease,[66] hemophilia,[67] cystic fibrosis,[68] Duchenne's muscular dystrophy,[69] Huntington's,[70][71] and heart disease.[72] CRISPR may have applications in tissue engineering and regenerative medicine, such as by creating human blood vessels that lack expression of MHC class II proteins, which often cause transplant rejection.[73]

CRISPR-Cas-based "RNA-guided nucleases" can be used to target virulence factors, genes encoding antibiotic resistance and other medically relevant sequences of interest. This technology thus represents a novel form of antimicrobial therapy and a strategy by which to manipulate bacterial populations.[74][75] Recent studies suggested a correlation between the interfering of the CRISPR-Cas locus and acquisition of antibiotic resistance[76] This system provides protection of bacteria against invading foreign DNA, such as transposons, bacteriophages and plasmids. This system was shown to be a strong selective pressure for the acquisition of antibiotic resistance and virulence factor in bacterial pathogens.[76]

Therapies based on CRISPRCas3 gene editing technology delivered by engineered bacteriophages could be used to destroy targeted DNA in pathogens. [77] Cas3 is more destructive than the better known Cas9[78][79]

Research suggests that CRISPR is an effective way to limit replication of multiple herpesviruses. It was able to eradicate viral DNA in the case of Epstein-Barr virus (EBV). Anti-herpesvirus CRISPRs have promising applications such as removing cancer-causing EBV from tumor cells, helping rid donated organs for immunocompromised patients of viral invaders, or preventing cold sore outbreaks and recurrent eye infections by blocking HSV-1 reactivation. As of August2016[update], these were awaiting testing.[80]

CRISPR may revive the concept of transplanting animal organs into people. Retroviruses present in animal genomes could harm transplant recipients. In 2015, a team eliminated 62 copies of a retrovirus's DNA from the pig genome in a kidney epithelial cell.[81] Researchers recently demonstrated the ability to birth live pig specimens after removing these retroviruses from their genome using CRISPR for the first time.[82]

As of 2016[update] CRISPR had been studied in animal models and cancer cell lines, to learn if it can be used to repair or thwart mutated genes that cause cancer.[83]

The first clinical trial involving CRISPR started in 2016. It involved removing immune cells from people with lung cancer, using CRISPR to edit out the gene expressed PD-1, then administrating the altered cells back to the same person. 20 other trials were under way or nearly ready, mostly in China, as of 2017[update].[64]

In 2016, the United States Food and Drug Administration (FDA) approved a clinical trial in which CRISPR would be used to alter T cells extracted from people with different kinds of cancer and then administer those engineered T cells back to the same people.[84]

Using "dead" versions of Cas9 (dCas9) eliminates CRISPR's DNA-cutting ability, while preserving its ability to target desirable sequences. Multiple groups added various regulatory factors to dCas9s, enabling them to turn almost any gene on or off or adjust its level of activity.[81] Like RNAi, CRISPR interference (CRISPRi) turns off genes in a reversible fashion by targeting, but not cutting a site. The targeted site is methylated, epigenetically modifying the gene. This modification inhibits transcription. These precisely placed modifications may then be used to regulate the effects on gene expressions and DNA dynamics after the inhibition of certain genome sequences within DNA. Within the past few years, epigenetic marks in different human cells have been closely researched and certain patterns within the marks have been found to correlate with everything ranging from tumor growth to brain activity.[6] Conversely, CRISPR-mediated activation (CRISPRa) promotes gene transcription.[85] Cas9 is an effective way of targeting and silencing specific genes at the DNA level.[86] In bacteria, the presence of Cas9 alone is enough to block transcription. For mammalian applications, a section of protein is added. Its guide RNA targets regulatory DNA sequences called promoters that immediately precede the target gene.[87]

Cas9 was used to carry synthetic transcription factors that activated specific human genes. The technique achieved a strong effect by targeting multiple CRISPR constructs to slightly different locations on the gene's promoter.[87]

In 2016, researchers demonstrated that CRISPR from an ordinary mouth bacterium could be used to edit RNA. The researchers searched databases containing hundreds of millions of genetic sequences for those that resembled Crispr genes. They considered the fusobacteria Leptotrichia shahii. It had a group of genes that resembled CRISPR genes, but with important differences. When the researchers equipped other bacteria with these genes, which they called C2c2, they found that the organisms gained a novel defense.[88]

Many viruses encode their genetic information in RNA rather than DNA that they repurpose to make new viruses. HIV and poliovirus are such viruses. Bacteria with C2c2 make molecules that can dismember RNA, destroying the virus. Tailoring these genes opened any RNA molecule to editing.[88]

CRISPR-Cas systems can also be employed for editing of micro-RNA and long-noncoding RNA genes in plants.[89]

Gene drives may provide a powerful tool to restore balance of ecosystems by eliminating invasive species. Concerns regarding efficacy, unintended consequences in the target species as well as non-target species have been raised particularly in the potential for accidental release from laboratories into the wild. Scientists have proposed several safeguards for ensuring the containment of experimental gene drives including molecular, reproductive, and ecological.[90] Many recommend that immunization and reversal drives be developed in tandem with gene drives in order to overwrite their effects if necessary.[91] There remains consensus that long-term effects must be studied more thoroughly particularly in the potential for ecological disruption that cannot be corrected with reversal drives.[92]

Unenriched sequencing libraries often have abundant undesired sequences. Cas9 can specifically deplete the undesired sequences with double strand breakage with up to 99% efficiency and without significant off-target effects as seen with restriction enzymes. Treatment with Cas9 can deplete abundant rRNA while increasing pathogen sensitivity in RNA-seq libraries.[93]

As of November2013[update], SAGE Labs (part of Horizon Discovery group) had exclusive rights from one of those companies to produce and sell genetically engineered rats and non-exclusive rights for mouse and rabbit models.[94] By 2015[update], Thermo Fisher Scientific had licensed intellectual property from ToolGen to develop CRISPR reagent kits.[95]

As of December2014[update], patent rights to CRISPR were contested. Several companies formed to develop related drugs and research tools.[96] As companies ramp up financing, doubts as to whether CRISPR can be quickly monetized were raised.[97] In February 2017 the US Patent Office ruled on a patent interference case brought by University of California with respect to patents issued to the Broad Institute, and found that the Broad patents, with claims covering the application of CRISPR-Cas9 in eukaryotic cells, were distinct from the inventions claimed by University of California.[98][99][100]Shortly after, University of California filed an appeal of this ruling.[101][102]

In March 2017, the European Patent Office (EPO) announced its intention to allow broad claims for editing all kinds of cells to Max-Planck Institute in Berlin, University of California, and University of Vienna,[103][104] and in August 2017, the EPO announced its intention to allow CRISPR claims in a patent application that MilliporeSigma had filed.[103] As of August2017[update] the patent situation in Europe was complex, with MilliporeSigma, ToolGen, Vilnius University, and Harvard contending for claims, along with University of California and Broad.[105]

As of March 2015, multiple groups had announced ongoing research to learn how they one day might apply CRISPR to human embryos, including labs in the US, China, and the UK, as well as US biotechnology company OvaScience.[106] Scientists, including a CRISPR co-discoverer, urged a worldwide moratorium on applying CRISPR to the human germline, especially for clinical use. They said "scientists should avoid even attempting, in lax jurisdictions, germline genome modification for clinical application in humans" until the full implications "are discussed among scientific and governmental organizations".[107][108] These scientists support further low-level research on CRISPR and do not see CRISPR as developed enough for any clinical use in making heritable changes to humans.[109]

In April 2015, Chinese scientists reported results of an attempt to alter the DNA of non-viable human embryos using CRISPR to correct a mutation that causes beta thalassemia, a lethal heritable disorder.[110][111] The study had previously been rejected by both Nature and Science in part because of ethical concerns.[112] The experiments resulted in successfully changing only some of the intended genes, and had off-target effects on other genes. The researchers stated that CRISPR is not ready for clinical application in reproductive medicine.[112] In April 2016, Chinese scientists were reported to have made a second unsuccessful attempt to alter the DNA of non-viable human embryos using CRISPR - this time to alter the CCR5 gene to make the embryo HIV resistant.[113]

In December 2015, an International Summit on Human Gene Editing took place in Washington under the guidance of David Baltimore. Members of national scientific academies of America, Britain and China discussed the ethics of germline modification. They agreed to support basic and clinical research under certain legal and ethical guidelines. A specific distinction was made between somatic cells, where the effects of edits are limited to a single individual, versus germline cells, where genome changes could be inherited by descendants. Heritable modifications could have unintended and far-reaching consequences for human evolution, genetically (e.g. gene/environment interactions) and culturally (e.g. Social Darwinism). Altering of gametocytes and embryos to generate inheritable changes in humans was defined to be irresponsible. The group agreed to initiate an international forum to address such concerns and harmonize regulations across countries.[114]

In November 2018, Jiankui He announced that he had edited two human embryos, to attempt to disable the gene for CCR5, which codes for a receptor that HIV uses to enter cells. He said that twin girls, Lulu and Nana, had been born a few weeks earlier. He said that the girls still carried functional copies of CCR5 along with disabled CCR5 (mosaicism) and were still vulnerable to HIV. The work was widely condemned as unethical, dangerous, and premature.[115] An international group of scientists called for a global moratorium on genetically editing human embryos.[116]

Policy regulations for the CRISPR-Cas9 system vary around the globe. In February 2016, British scientists were given permission by regulators to genetically modify human embryos by using CRISPR-Cas9 and related techniques. However, researchers were forbidden from implanting the embryos and the embryos were to be destroyed after seven days.[117]

The US has an elaborate, interdepartmental regulatory system to evaluate new genetically modified foods and crops. For example, the Agriculture Risk Protection Act of 2000 gives the USDA the authority to oversee the detection, control, eradication, suppression, prevention, or retardation of the spread of plant pests or noxious weeds to protect the agriculture, environment and economy of the US. The act regulates any genetically modified organism that utilizes the genome of a predefined "plant pest" or any plant not previously categorized.[118] In 2015, Yinong Yang successfully deactivated 16 specific genes in the white button mushroom, to make them non-browning. Since he had not added any foreign-species (transgenic) DNA to his organism, the mushroom could not be regulated by the USDA under Section 340.2.[119] Yang's white button mushroom was the first organism genetically modified with the CRISPR-Cas9 protein system to pass US regulation.[120] In 2016, the USDA sponsored a committee to consider future regulatory policy for upcoming genetic modification techniques. With the help of the US National Academies of Sciences, Engineering and Medicine, special interests groups met on April 15 to contemplate the possible advancements in genetic engineering within the next five years and any new regulations that might be needed as a result.[121] The FDA in 2017 proposed a rule that would classify genetic engineering modifications to animals as "animal drugs", subjecting them to strict regulation if offered for sale, and reducing the ability for individuals and small businesses to make them profitably.[122][123]

In China, where social conditions sharply contrast with the west, genetic diseases carry a heavy stigma.[124] This leaves China with fewer policy barriers to the use of this technology.[125][126]

In 2012, and 2013, CRISPR was a runner-up in Science Magazine's Breakthrough of the Year award. In 2015, it was the winner of that award.[81] CRISPR was named as one of MIT Technology Review's 10 breakthrough technologies in 2014 and 2016.[127][128] In 2016, Jennifer Doudna, Emmanuelle Charpentier, along with Rudolph Barrangou, Philippe Horvath, and Feng Zhang won the Gairdner International award. In 2017, Jennifer Doudna and Emmanuelle Charpentier were awarded the Japan Prize for their revolutionary invention of CRISPR-Cas9 in Tokyo, Japan. In 2016, Emmanuelle Charpentier, Jennifer Doudna, and Feng Zhang won the Tang Prize in Biopharmaceutical Science.[129]

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CRISPR gene editing - Wikipedia

While ethicists debate the applications of blockbuster gene-editing tool Crispr in human healthcare, an inventor of the tool believes it has a more immediate application: improving our food.

"I think in the next five years the most profound thing we'll see in terms of Crispr's effects on people's everyday lives will be in the agricultural sector," Jennifer Doudna, the University of California Berkeley geneticist who unearthed Crispr in early experiments with bacteria in 2012, told Business Insider.

Crispr has dozens of potential uses, from treating diseases like sickle cell to certain inherited forms of blindness. The tool recently made headlines when a scientist in China reportedly used it to edit the DNA of a pair of twin baby girls.

Then there are Crispr's practical applications the kinds of things we might expect to see in places like grocery stores and farmers' fields within a decade, according to Doudna.

Crispr's appeal in food is straightforward: it's cheaper and easier than traditional breeding methods, including those that are used to make genetically modified crops (also known as GMOs) currently. It's also much more precise. Where traditional breeding methods hack away at a crop's genome with a dull blade, tools like Crispr slice and reshape with scalpel-like precision.

Want a mushroom that doesn't brown? A corn crop that yields more food per acre? Both already exist, though they haven't yet made it to consumers' plates. What about a strawberry with a longer shelf life or tomatoes that do a better job of staying on the vine?

"I think all of those things are coming relatively quickly," Doudna said.

Read more: The 10 people transforming healthcare

Work on Crispr'd produce has been ongoing for about half a decade, but it's only recently that US regulators have created a viable path for Crispr'd products to come to market.

Back in 2016, researchers at Penn State used Crispr to make mushrooms that don't brown. Last spring, gene-editing startup Pairwise scored $125 million from agricultural giant Monsanto to work on Crispr'd produce with the goal of getting it in grocery stores within the decade. A month later, Stefan Jansson, the chief of the plant physiology department at Sweden's Umea University, grew and ate the world's first Crispr'd kale.

More recently, several Silicon Valley startups have been experimenting with using Crispr to make lab-grown meat.

Read more: Startups backed by celebrities like Bill Gates are using Crispr to make meat without farms

Memphis Meats, a startup with backing from notable figures like Bill Gates and Richard Branson that has made real chicken strips and meatball prototypes from animal cells (and without killing any animals), is using the tool. So is New Age Meats, another San Francisco-based startup that aims to create real meat without slaughter.

Last spring, the US Department of Agriculture issued a new ruling on crops that exempts many Crispr-modified crops from the oversight that accompanies traditional GMOs. So long as the edited DNA in those crops could also have been created using traditional breeding techniques, the Crispr'd goods are not subject to those additional regulatory steps, according to the agency.

"With this approach, USDA seeks to allow innovation when there is no risk present," secretary of agriculture Sonny Perdue said in a statement. Genome editing tools like Crispr, he added, "will help farmers do what we aspire to do at USDA: do right and feed everyone."

Read more: A controversial technology could save us from starvation if we let it

Although several researchers and scientists have cheered the decision, many anti-GMO activists have not been pleased.

Despite the pushback, Doudna believes that Crispr'd food could help dispel some of the fear around GMOs and increase awareness about the role of science in agriculture.

"I hope this brings that discussion into a realm where we can talk about it in a logical way," she said. "Isn't it better to have technology that allows for precise manipulation of a plant genome, rather than relying on random changes?"

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