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Genetic data show mainly men migrated from the Pontic steppe to ... Science Daily A new study, looking at the sex-specifically inherited X chromosome of prehistoric human remains, shows that hardly any women took part in the extensive ... and more »

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Genetic data show mainly men migrated from the Pontic steppe to ... - Science Daily

A Yamnaya skeleton from a grave in the Russian steppe, which was the homeland of men who migrated to Europe.

XVodolazx/Wikimedia Commons

By Ann GibbonsFeb. 21, 2017 , 12:00 PM

Call it an ancient thousand man march. Early Bronze Age men from the vast grasslands of the Eurasian steppe swept into Europe on horseback about 5000 years agoand may have left most women behind. This mostly male migration may have persisted for several generations, sending men into the arms of European women who interbred with them, and leaving a lasting impact on the genomes of living Europeans.

It looks like males migrating in war, with horses and wagons, says lead author and population geneticist Mattias Jakobsson of Uppsala University in Sweden.

Europeans are the descendants of at least three major migrations of prehistoric people. First, a group of hunter-gatherers arrived in Europe about 37,000 years ago. Then, farmers began migrating from Anatolia (a region including present-day Turkey) into Europe 9000 years ago, but they initially didnt intermingle much with the local hunter-gatherers because they brought their own families with them. Finally, 5000 to 4800 years ago, nomadic herders known as the Yamnaya swept into Europe. They were an early Bronze Age culture that came from the grasslands, or steppes, of modern-day Russia and Ukraine, bringing with them metallurgy and animal herding skills and, possibly,Proto-Indo-European, themysterious ancestral tonguefrom which all of todays 400 Indo-European languages spring. Theyimmediately interbred with local Europeans, who were descendants of both the farmers and hunter-gatherers. Within a few hundred years, the Yamnaya contributed to at least half of central Europeans genetic ancestry.

To find out why this migration of Yamnaya had such a big impact on European ancestry, researchers turned to genetic data from earlier studies of archaeological samples. They analyzed differences in DNA inherited by 20 ancient Europeans who lived just after the migration of Anatolian farmers (6000 to 4500 years ago) and 16 who lived just after the influx of Yamnaya (3000 to 1000 years ago). The team zeroed in on differences in the ratio of DNA inherited on their X chromosomes compared with the 22 chromosomes that do not determine sex, the so-called autosomes. This ratio can reveal the proportion of men and women in an ancestral population, because women carry two X chromosomes, whereas men have only one.

Europeans who were alive from before the Yamnaya migration inherited equal amounts of DNA from Anatolian farmers on their X chromosome and their autosomes, the team reports today in the Proceedings of the National Academy of Sciences. This means roughly equal numbers of men and women took part in the migration of Anatolian farmers into Europe.

But when the researchers looked at the DNA later Europeans inherited from the Yamnaya, they found that Bronze Age Europeans had far less Yamnaya DNA on their X than on their other chromosomes. Using a statistical method developed by graduate student Amy Goldberg in the lab of population geneticist Noah Rosenberg at Stanford University in Palo Alto, California, the team calculated that there were perhaps 10 men for every woman in the migration of Yamnaya men to Europe (with a range of five to 14 migrating men for every woman). That ratio is extremeeven more lopsided than the mostly male wave of Spanish conquistadores who came by ship to the Americas in the late 1500s, Goldberg says.

Such a skewed ratio raises red flags for some researchers, who warn it is notoriously difficult to estimate the ratio of men to women accurately in ancient populations. But if confirmed, one explanation is that the Yamnaya men were warriors who swept into Europe on horses or drove horse-drawn wagons; horses had been recently domesticated in the steppe and the wheel was a recent invention. They may have been more focused on warfare, with faster dispersal because of technological inventions says population geneticist Rasmus Nielsen of the University of California, Berkeley, who is not part of the study.

But warfare isnt the only explanation. The Yamnaya men could have been more attractive mates than European farmers because they had horses and new technologies, such as copper hammers that gave them an advantage, Goldberg says.

The finding that Yamnaya men migrated for many generations also suggests that all was not right back home in the steppe. It would imply a continuing strongly negative push factor within the steppes, such as chronic epidemics or diseases, says archaeologist David Anthony of Hartwick College in Oneonta, New York, who was not an author of the new study. Or, he says it could be the beginning of cultures that sent out bands of men to establish new politically aligned colonies in distant lands, as in later groups of Romans or Vikings.

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Thousands of horsemen may have swept into Bronze Age Europe, transforming the local population - Science Magazine

Although common, male baldness can have negative psychological effects and some studies have even linked it to a handful of serious illnesses. New research identifies the genetic variants involved in the condition, which could eventually enable researchers to predict a person's chances of hair loss.

Male baldness - also referred to as androgenetic alopecia or male pattern baldness (MPB) - affects a significant number of people in the United States, as the condition accounts for over 95 percent of all hair loss in men.

According to the American Hair Loss Association, two thirds of U.S. adults will be affected by MPB to a certain degree by the age of 35, and around 85 percent of men will have experienced significant hair loss by the age of 50.

A lot of these men are seriously affected by the condition, which can have a negative effect on a person's self-image, as well as on their interpersonal relationships.

Additionally, some genetic studies have even associated MPB with negative clinical outcomes such as prostate cancer and cardiovascular disease.

A new study - led by Saskia Hagenaars and David Hill of the University of Edinburgh in the United Kingdom - explores the genetic basis for the condition. The findings were published in the journal PLOS Genetics.

Scientists analyzed the genomic and health data of more than 52,000 men enrolled in the UK Biobank - an international health resource offering health information on more than 500,000 individuals.

The team located more than 250 independent genetic regions linked to severe hair loss.

The researchers split the 52,000 participants into two groups: a so-called discovery sample of 40,000 people and a target sample of 12,000 individuals. Based on the genetic variants that separated those with no hair loss from those with severe hair loss, the team designed an algorithm aimed to predict who would develop MPB.

The algorithmic baldness predictor is based on a genetic score, and although accurate predictions are still a long way off, the results of this study might soon enable researchers to identify subgroups of the population that are particularly prone to hair loss.

In the present study, researchers found that 14 percent of the participants with a submedian genetic score had severe MPB, and 39 percent had no hair loss. By contrast, 58 percent of those scoring in the top 10 percent on the polygenic score had moderate to severe MPB.

Co-lead author Saskia Hagenaars - a Ph.D. student at the University of Edinburgh's Centre for Cognitive Aging and Cognitive Epidemiology - comments on the findings:

"We identified hundreds of new genetic signals," Hagenaars says. "It was interesting to find that many of the genetics signals for male pattern baldness came from the X chromosome, which men inherit from their mothers."

The study's other lead author, Dr. David Hill, notes that the study did not collect data on the age of baldness onset, but only on hair loss pattern. However, he adds that, "we would expect to see an even stronger genetic signal if we were able to identify those with early-onset hair loss."

To the authors' knowledge, this is the largest genetic study of MPB to date.

The study's principal investigator, Dr. Riccardo Marioni, from the University of Edinburgh's Centre for Genomic and Experimental Medicine, explains the significance of the findings:

"We are still a long way from making an accurate prediction for an individual's hair loss pattern. However, these results take us one step closer. The findings pave the way for an improved understanding of the genetic causes of hair loss."

Learn how a drug promises robust new hair growth.

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Genetic basis for male baldness identified in large-scale study - Medical News Today

A new study has found over 280 genes associated with male-pattern baldness.

These genes could be used to predict a man's chance of hair loss or possibly provide targets for drug development in the future.

The research, published in PLOS Genetics, is the largest genomic study of baldness to date. Researchers studied the DNA of more than 52,000 men aged between 4069 years old enrolled in the UK Biobank, looking for genes associated with baldness.

'We identified hundreds of new genetic signals,' Saskia Hagenaars, a PhD student at the University of Edinburgh and co-lead author, said. 'It was interesting to find that many of the genetics signals for male-pattern baldness came from the X chromosome, which men inherit from their mothers.'

Many of the 287 genes linked with hair loss were related to hair growth and development. The researchers used these genes to try to predict the chance that a man will go bald, and found that almost 60 percent of those with the most number of hair loss genes showed signs of moderate to serious balding. However, the authors state that predictions for individuals are still 'relatively crude'.

'Data were collected on hair-loss pattern but not age of onset; we would expect to see an even stronger genetic signal if we were able to identify those with early-onset hair loss,' said Dr David Hill, University of Edinburgh, who co-led the research.

Male-pattern baldness affects around half of all men by the age of 50. The condition is hereditary and thought to be linked to levels of a certain male sex hormone. Previous genetic studies have also associated male-pattern baldness with prostate cancer and heart disease.

The study's principal investigator, Dr Riccardo Marioniof theUniversity of Edinburgh, said: 'We are still a long way from making an accurate prediction for an individual's hair-loss pattern. However, these results take us one step closer. The findings pave the way for an improved understanding of the genetic causes of hair loss.'

The study was based on information from the first release of data from the UK Biobank in 2015. The authors say that the release of data from the full cohort will enable them to further refine their predictions of male-pattern baldness and investigate its genetic basis.

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Baldness linked to over 280 genes - BioNews

February 21, 2017

A new study, looking at the sex-specifically inherited X chromosome of prehistoric human remains, shows that hardly any women took part in the extensive migration from the Pontic-Caspian Steppe approximately 5,000 years ago. The great migration that brought farming practices to Europe 4,000 years earlier, on the other hand, consisted of both women and men. The difference in sex bias suggests that different social and cultural processes drove the two migrations.

Genetic data suggest that modern European ancestry represents a mosaic of ancestral contributions from multiple waves of prehistoric migration events. Recent studies of genomic variation in prehistoric human remains have demonstrated that two mass migration events are particularly important to understanding European prehistory: the Neolithic spread of agriculture from Anatolia starting around 9,000 years ago, and migration from the Pontic-Caspian Steppe around 5,000 years ago. These migrations are coincident with large social, cultural, and linguistic changes, and each has been inferred to have replaced more than half of the contemporaneous gene pool of resident Central Europeans.

Dramatic events in human prehistory can be investigated using patterns of genetic variation among the people that lived in those times. In particular, studies of differing female and male demographic histories on the basis of ancient genomes can provide information about complexities of social structures and cultural interactions in prehistoric populations.

Researchers from Uppsala and Stanford University investigated the genetic ancestry on the sex-specifically inherited X chromosome and the autosomes in 20 early Neolithic and 16 Late Neolithic/Bronze Age human remains. Contrary to previous hypotheses suggesting patrilocality (social system in which a family resides near the man's parents) of many agricultural populations, they found no evidence of sex-biased admixture during the migration that spread farming across Europe during the early Neolithic.

For later migrations from the Pontic steppe during the early Bronze Age, however, we find a dramatic male bias. There are simply too few X-chromosomes from the migrants, which points to around ten migrating males for every migrating female, says Mattias Jakobsson, professor of Genetics at the Department of Organismal Biology, Uppsala University.

The research group found evidence of ongoing, primarily male, migration from the steppe to central Europe over a period of multiple generations, with a level of sex bias that excludes a pulse migration during a single generation.

The contrasting patterns of sex-specific migration during these two migrations suggest a view of differing cultural histories in which the Neolithic transition was driven by mass migration of both males and females in roughly equal numbersperhaps whole familieswhereas the later Bronze Age migration and cultural shift were instead driven by male migration.

Explore further: Baltic hunter-gatherers began farming without influence of migration, ancient DNA suggests

More information: "Ancient X chromosomes reveal contrasting sex bias in Neolithic and Bronze Age Eurasian migrations," PNAS, DOI: 10.1073/pnas.1616392114 , http://www.pnas.org/content/early/2017/02/17/1616392114.abstract

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Genetic data show mainly men migrated from the Pontic steppe to Europe 5000 years ago - Phys.Org

It all comes from your X chromosome (Picture: Getty)

Getting a bit smooth up top? Judging on how you feel about it, your mum is the one you should be blaming /thanking.

Researchers at the University of Edinburgh have found that men inherit most of their baldness genes from their mums side of the family.

For what is the largest ever analysis of hair loss, scientists looked at the DNA of 52,000 men.

They identified almost 300 genes that could contribute to male pattern baldness most of which come from the X chromosome.

Saskia Hagenaars, who jointly led the research, said: We identified hundreds of new genetic signals.

It was interesting to find that many of the genetics signals for male pattern baldness came from the X chromosome, which men inherit from their mothers.

Before this research, published in PLOS Genetics, scientists had only identified a handful of genes related to baldness.

The studys principle investigator, Dr Riccardo Marioni, added: We are still a long way from making an accurate prediction for an individuals hair loss pattern.

However, these results take us one step closer.

The findings pave the way for an improved understanding of the genetic causes of hair loss.

More here:
Men inherit male pattern baldness from their mum's side of the family ... - Metro

More than 200 new genetic markers linked with male pattern baldness have been identified, according to a new study from the United Kingdom.

The findings greatly increase the number of known genetic markers linked with baldness in men; a previous large study identified just eight such markers.

The researchers in the new study were also able to use their set of genetic markers to predict mens chances of severe hair loss, although the scientists noted that their results apply more to large populations of people than to any given individual.

We are still a long way from making an accurate prediction for an individuals hair-loss pattern. However, these results take us one step closer, study co-author Riccardo Marioni, of the University of Edinburghs Centre for Genomic and Experimental Medicine, said in a statement. The findings pave the way for an improved understanding of the genetic causes of hair loss, Marioni said. [5 Myths About the Male Body]

In the study, the researchers analyzed information from more than 52,000 men ages 40 to 69 years in the United Kingdom. Of these men, about 32 percent said they had no hair loss, 23 percent said they had slight hair loss, 27 percent said they had moderate hair loss and 18 percent said they had severe hair loss

The researchers then analyzed participants genomes, looking for genetic variations, known as single-nucleotide polymorphisms, or SNPs, that were linked with severe hair loss. That search revealed 287 genetic variations, located on more than 100 genes, that were linked with severe hair loss.

Many of the genetic variations were located on or near genes that have previously been linked with hair growth, hair graying or the biological structures involved in making hair, the researchers said.

Forty of the genetic variations were located on the X chromosome, which men inherit from their mothers, the researchers said. One of the genes on the X chromosome the gene for the androgen receptor, which binds to the hormone testosterone was strongly linked with severe hair loss. Previous studies have also pinpointed this gene as tied to male pattern baldness.

The researchers then created a formula, which resulted in a genetic risk score, to try to predict the chances of severe hair loss in the men. Among those men with a below-average score, 39 percent had no hair loss and 14 percent had severe hair loss. In contrast, among those with a high score that put them in the top 10 percent of those in the study, 58 percent had moderate-to-severe hair loss.

The researchers noted that in the study, they did not collect information on the age at which the men started losing their hair. The scientists said they would expect to see even stronger genetic associations with hair loss if they were able to include information about which men experienced early onset hair loss.

As more information from these participants becomes available, the researchers may be able to further refine their predictions, they said.

The study was published today (Feb. 14) in the journal PLOS Genetics.

Original article on Live Science.

Read more:
Experts Are One Step Closer To Predicting A Man's Risk For Hair Loss - Huffington Post

More than 200 new genetic markers linked with male pattern baldness have been identified, according to a new study from the United Kingdom.

The findings greatly increase the number of known genetic markers linked with baldness in men; a previous large study identified just eight such markers.

The researchers in the new study were also able to use their set of genetic markers to predict men's chances of severe hair loss, although the scientists noted that their results apply more to large populations of people than to any given individual.

"We are still a long way from making an accurate prediction for an individual's hair-loss pattern. However, these results take us one step closer," study co-author Riccardo Marioni, of the University of Edinburgh's Centre for Genomic and Experimental Medicine, said in a statement. "The findings pave the way for an improved understanding of the genetic causes of hair loss," Marioni said. [5 Myths About the Male Body]

In the study, the researchers analyzed information from more than 52,000 men ages 40 to 69 years in the United Kingdom. Of these men, about 32 percent said they had no hair loss, 23 percent said they had slight hair loss, 27 percent said they had moderate hair loss and 18 percent said they had severe hair loss

The researchers then analyzed participants' genomes, looking for genetic variations, known as single-nucleotide polymorphisms, or SNPs, that were linked with severe hair loss. That search revealed 287 genetic variations, located on more than 100 genes, that were linked with severe hair loss.

Many of the genetic variations were located on or near genes that have previously been linked with hair growth, hair graying or the biological structures involved in making hair, the researchers said.

Forty of the genetic variations were located on the X chromosome, which men inherit from their mothers, the researchers said. One of the genes on the X chromosome the gene for the androgen receptor, which binds to the hormone testosterone was strongly linked with severe hair loss. Previous studies have also pinpointed this gene as tied to male pattern baldness.

The researchers then created a formula, which resulted in a genetic "risk score," to try to predict the chances of severe hair loss in the men. Among those men with a below-average score, 39 percent had no hair loss and 14 percent had severe hair loss. In contrast, among those with a high score that put them in the top 10 percent of those in the study, 58 percent had moderate-to-severe hair loss.

The researchers noted that in the study, they did not collect information on the age at which the men started losing their hair. The scientists said they would expect to see even stronger genetic associations with hair loss if they were able to include information about which men experienced early onset hair loss.

As more information from these participants becomes available, the researchers may be able to further refine their predictions, they said.

The study was published today (Feb. 14) in the journal PLOS Genetics.

Original article on Live Science.

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More Than 200 Baldness-Linked Genetic Markers Found - Yahoo News

Men's Health

Can Your Anxiety Impact How Long You Last In Bed? Men's Health To rule out the influence of genetics, the researchers only studied male twins and brothers of twins. After analyzing their responses, the researchers found no link between anxiety symptoms reported in 2006 with later reports of premature ejaculation ...

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Can Your Anxiety Impact How Long You Last In Bed? - Men's Health

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Women in Data Science conference highlights female participation in male-dominated field Daily Free Press (subscription) Later in the day, Caroline Uhler, a professor at MIT's Institute for Data, Systems, and Society, shared her research on weather forecasting models and her work with genetics. Audience members listened, taking notes on Uhler's data-driven research and ...

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Women in Data Science conference highlights female participation in male-dominated field - Daily Free Press (subscription)

Shutterstock/UPROXX

Why is contraception the burden of women? Male contraception would seem to be a much easier way of having sex for fun and not sticking a woman with the baby, but its rarely been on the minds of scientists in the past. That may be about to change, especially with the recent success of Vasalgel in a clinical trial. But why did it take so long, and why is it going so slowly?

Currently contraception takes three forms when it comes to men: Withdrawal, vascetomy, or condoms. Pulling out requires experience and control, making it less than ideal for an act all about losing control. Vasectomy works, but is, well, a rather permanent solution most people dont want to resort to. And condoms generally work, and have the bonus of helping prevent STIs.

That said, contraceptive options for women tend to be riskier, healthwise. Hormonal birth control may, depending on your genetics, increase your risk of stroke, and other side effects of the pill, especially the psychological ones, had been downplayed or even covered up for years or decades. Tubal ligation is more dangerous than vasectomy, albeit only by a small margin, and also a permanent solution where one may not be wanted. And IUDs have rare, but potentially serious, risks. Simply put, biology makes it much easier for men to use contraceptives, but historically, its been the womans job.

The main issue is that where women produce one cell a month, men crank out literally over a thousand sperm per second. That makes male birth control inherently more hit-or-miss since, despite making millions of them, you only need one to get pregnant. And, it has to be said, theres also the social aspect: Men dont get pregnant, and its easier to simply stick the woman with the responsibility and walk away. The history of birth control is littered with ugly incidents where sex without babies was seen as more important than womens health.

That doesnt mean, however, that men havent been trying, and even succeeding to some degree. The ancient Greeks mixed hemp seeds and rue in alcohol to lower sperm count, a method which worked in rat studies conducted thousands of years later. Gossypol, a polymer found in cottonseed oil used for cooking, turned out to be effective, but had a high risk of permanent infertility. And recently, the folklore that papaya seeds reduce fertility turned out to be accurate.

The problem is that the fields had several high profile failures. For example, a few months ago, Facebook had a good giggle at the idea of fragile men unable to handle the side effects of an experimental set of hormonal birth control shots. But that ignored that as the study has scaled up, it had gotten more and more reports of excessively increased libido from more than a third of study participants and 20% reporting mood disorders. That meant one of two things: The drug was riskier than previously thought, or something in the trial had gone wrong.

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There are, however, a host of other options. Calcium channel blockers, encouraging the immune system to attack sperm, and even an alpha blocker that simply prevents ejaculation are all out there and being tested. And noninvasive surgical options, like the aforementioned Vasalgel, which is already in human trials in India, and a treatment blasting the testicles with ultrasound to kill sperm, are also showing promise.

So whats the issue? Why is research so slow? In a word? Trust. Women have repeatedly expressed a discomfort in trusting men to be in charge of their reproductive destiny. In fact, it can even be a form of domestic violence: In 2010, 10% of men and 9% of women report theyve been the targets of reproductive coercion, in which someone is forced into a pregnancy by means of sabotaging their birth control, or being impregnated without their consent. And only recently have the courts viewed removing a condom during sex as a serious crime.

That, combined with the fears of some men that male birth control will make them less of a man, can be a difficult hurdle for some to jump. That said, men should be allowed to take more control of their reproductive destiny. And medical science finally seems ready to give them just that.

Excerpt from:
Male Contraceptives Have A Messy History And A Bright Future - Yahoo News

Male infertility is a multifactorial disorder with impressively genetic basis; besides, sperm abnormalities are the cause of numerous cases of male infertility. In this study, we evaluated the genetic variants in exons 4 and 5 and their intron-exon boundaries in RABL2B gene in infertile men with oligoasthenoteratozoospermia (OAT) and immotile short tail sperm (ISTS) defects to define if there is any association between these variants and human male infertility.

To this purpose, DNA was extracted from peripheral blood and after PCR reaction and sequencing, the results of sequenced segments were analyzed. In the present study, 30 infertile men with ISTS defect and 30 oligoasthenoteratozoospermic infertile men were recruited. All men were of Iranian origin and it took 3years to collect patient's samples with ISTS defect.

As a result, the 50776482 delC intronic variant (rs144944885) was identified in five patients with oligoasthenoteratozoospermia defect and one patient with ISTS defect in heterozygote form. This variant was not identified in controls. The allelic frequency of the 50776482 delC variant was significantly statistically higher in oligoasthenoteratozoospermic infertile men (p<0.05). Bioinformatics studies suggested that the 50776482 delC allele would modify the splicing of RABL2B pre-mRNA. In addition, we identified a new genetic variant in RABL2B gene.

According to the present study, 50776482 delC allele in the RABL2B gene could be a risk factor in Iranian infertile men with oligoasthenoteratozoospermia defect, but more genetic studies are required to understand the accurate role of this variant in pathogenesis of human male infertility.

Journal of assisted reproduction and genetics. 2017 Jan 30 [Epub ahead of print]

Seyedeh Hanieh Hosseini, Mohammad Ali Sadighi Gilani, Anahita Mohseni Meybodi, Marjan Sabbaghian

Department of Andrology, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran., Department of Genetics, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran., Department of Andrology, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran. .

PubMed http://www.ncbi.nlm.nih.gov/pubmed/28138870

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The impact of RABL2B gene (rs144944885) on human male infertility in patients with oligoasthenoteratozoospermia ... - UroToday

Tortoiseshell is a cat coat coloring named for its similarity to tortoiseshell material. Tortoiseshell cats are almost exclusively female.[1][2][3] Male tortoiseshells are rare and are usually sterile.[4][a]

Also called torties for short, tortoiseshell cats combine two colors other than white, either closely mixed or in larger patches.[2] The colors are often described as red and black, but the "red" patches can instead be orange, yellow, or cream,[2] and the "black" can instead be chocolate, grey, tabby, or blue.[2] Tortoiseshell cats with the tabby pattern as one of their colors are sometimes referred to as a torbie.[6]

"Tortoiseshell" is typically reserved for particolored cats with relatively small or no white markings. Those that are largely white with tortoiseshell patches are described as tricolor,[2] tortoiseshell-and-white (in the United Kingdom), or calico (in Canada and the United States).[7]

Tortoiseshell markings appear in many different breeds, as well as in non-purebred domestic cats.[7] This pattern is especially preferred in the Japanese Bobtail breed,[8] and exists in the Cornish Rex group.[9]

Tortoiseshell cats have particolored coats with patches of various shades of red and black, and sometimes white. A tortoiseshell can also have splotches of orange or gold, but these colors are rarer on the breed.[4] The size of the patches can vary from a fine speckled pattern to large areas of color. Typically, the more white a cat has, the more solid the patches of color. Dilution genes may modify the coloring, lightening the fur to a mix of cream and blue, lilac or fawn; and the markings on tortoiseshell cats are usually asymmetrical.[10]

Occasionally tabby patterns of black and brown (eumelanistic) and red (phaeomelanistic) colors are also seen. These patched tabbies are often called a tortie-tabby, torbie or, with large white areas, a caliby.[10] Not uncommonly there will be a "split face" pattern with black on one side of the face and orange on the other, with a dividing line running down the bridge of the nose. Tortoiseshell coloring can also be expressed in the point pattern, referred to as a "tortie point".[10]

Tortoiseshell and calico coats result from an interaction between genetic and developmental factors. The primary gene for coat color (B) for the colors brown, chocolate, cinnamon, etc., can be masked by the co-dominant gene for the orange color (O) which is on the X Chromosome and has two alleles, the orange (XO) and not-orange (Xo), that produce orange phaeomelanin and black eumelanin pigments, respectively. (NOTE: Typically, the X for the chromosome is assumed from context and the alleles are referred to by just the uppercase O for the orange, or lower case o for the not-orange.) The tortoiseshell and calico cats are indicated: Oo to indicate they are heterozygous on the O gene. The (B) and (O) genes can be further modified by a recessive dilute gene (dd) which softens the colors. Orange becomes cream, black becomes gray, etc. Various terms are used for specific colors, for example, gray is also called blue, orange is also called ginger. Therefore, a tortoiseshell cat may be a chocolate tortoiseshell or a blue/cream tortoiseshell or the like, based on the alleles for the (B) and (D) genes.

The cells of female cats, which like other mammalian females have two X chromosomes (XX), undergo the phenomenon of X-inactivation,[11][12] in which one or the other of the X-chromosomes is turned off at random in each cell in very early development. The inactivated X becomes a Barr body. Cells in which the chromosome carrying the orange (O) allele is inactivated express the alternative non-orange (o) allele, determined by the (B) gene. Cells in which the non-orange (o) allele is inactivated express the orange (O) allele. Pigment genes are expressed in melanocytes that migrate to the skin surface later in development. In bi-colored tortoiseshell cats, the melanocytes arrive relatively early, and the two cell types become intermingled, producing the characteristic brindled appearance consisting of an intimate mixture of orange and black cells, with occasional small diffuse spots of orange and black.

In tri-colored calico cats, a separate gene interacts developmentally with the coat color gene. This spotting gene produces white, unpigmented patches by delaying the migration of the melanocytes to the skin surface. There are a number of alleles of this gene that produce greater or lesser delays. The amount of white is artificially divided into mitted, bicolor, harlequin, and van, going from almost no white to almost completely white. In the extreme case, no melanocytes make it to the skin and the cat is entirely white (but not an albino). In intermediate cases, melanocyte migration is slowed, so that the pigment cells arrive late in development and have less time to intermingle. Observation of tri-color cats will show that, with a little white color, the orange and black patches become more defined, and with still more white, the patches become completely distinct. Each patch represents a clone of cells derived from one original cell in the early embryo.[13]

A male cat, like males of other therian mammals, has only one X and one Y chromosome (XY). That X chromosome does not undergo X-inactivation, and coat color is determined by which allele is present on the X. Accordingly, the cat's coat will be either entirely orange or non-orange. Very rarely (approximately 1 in 3,000[14]) a male tortoiseshell or calico is born. These animals typically have an extra X chromosome (XXY), a condition known in humans as Klinefelter syndrome, and their cells undergo an X-inactivation process like that in females. As in humans, these cats often are sterile because of the imbalance in sex chromosomes. Some male calico or tortoiseshell cats may be chimeras, which result from the fusion in early development of two (fraternal twin) embryos with different color genotypes. Others are mosaics, in which the XXY condition arises after conception and the cat is a mixture of cells with different numbers of X chromosomes.

In the folklore of many cultures, cats of the tortoiseshell coloration are believed to bring good luck.[15] Dating back to Celtic times, tortoiseshell cats have been perceived to bring good fortune into their homes. Even today, the Irish and Scottish believe stray tortoiseshell cats bring them luck.[16] In the United States, tortoiseshells are sometimes referred to as money cats.[17]

One study found that tortoiseshell owners frequently believe their cats have increased attitude ("tortitude");[18] however, little scientific evidence supports this.[19] According to celebrity cat expert Jackson Galaxy, tortoiseshell cats tend to have a much more distinct personality.[20]

See the rest here:
Tortoiseshell cat - Wikipedia

Knowing the real South Africa is to know, and be familiar with, the ambitious entrepreneurial spirit that runs through its tributaries and flows like a river into the heart of a nation. South Africans have always been opportunistic, from J.B.M Hertzog who founded Naspers, which is now Africa's largest company and globally the 7th largest internet company, to MTN and Discovery, both of which can now be found all over the world. We can even highlight the contributions of one of the world's most foremost thinkers and innovators, Elon Musk, the driving force behind SpaceX.

Recently, Ventureburn did an article on the Top Entrepreneurs Under 40 in South Africa, highlighting how this spirit continues to grow and is a far cry from fading anytime soon. But what differentiates the men and women who started these companies from those of us 'normal' people who would not regard ourselves as entrepreneurs?

Entrepreneurs are a rare breed of humans who choose to innovate and forge their ideas into successful business from the ground up. They're fearless and believe that what they are creating is going to change the world forever. And guess what, research shows that this could be genetic.

A recent study at Kings College in London, headed up by Scott Shane, identified that 37 to 48 per cent of the tendency to be an entrepreneur is genetic, and that the tendency to identify new business opportunities is in your genes. If you take this study as anything to go by, then this is remarkable as genetics account for almost half of what is a determining factor in becoming an entrepreneur.

What we know about genetics is that in some cases almost half of who we are is genetic, or how we are made, and the rest is down to environmental factors (in other words, what we do and how we live). This presents us all with an incredible opportunity to take control of our environment to use our genetic strengths to reach our goal. For some, and I would encourage any young South African with ambition to consider this path, that goal is entrepreneurship.

Take the environment in South Africa, for instance. South Africa is still a young country that is constantly growing, discovering who it is, and where its place in the world will be. This is what makes it the ideal environment for those predisposed, by either genetics, environment or desire, to entrepreneurship to thrive. It's not all dependent on your genotype, but a large proportion of it could be, according to this study, and this could be what drives certain people to tackle new, exciting business ventures that other people may be dissuaded from due to fear of failure and the unknown.

This isn't the only study that associates entrepreneurship with being genetics.

Nicos Nicolaou is a researcher who has been heading up these new discoveries that attempt to link genetics to entrepreneurship. Although they still require more research, which will come as the science around the human genome develops, their findings are interesting. They explain that there is a "single nucleotide polymorphism (rs1486011) of the DRD3 gene on chromosome 3 to be significantly associated with the tendency to be an entrepreneur. This result is the first evidence of the association of a specific gene with entrepreneurship."

Wouldn't you like to know if you had this gene, especially if you can already be considered an entrepreneur? I know I would, as it would be interesting to discover if my genes influenced me to start DNAFit, or any of my other business ventures.

I would also like to know if this gene is related to not requiring as much sleep as the average person - entrepreneurs never rest while there is opportunity to innovate and expand our ideas!

Going even deeper, Zhang did twin studies to find out if personality and gender play a role in the development of entrepreneurship as well. Their study can be regarded as verging on epigenetic as it uses the environmental impact, as well as genes.

It is based on "1285 pairs of identical twins (449 male and 836 female pairs) and 849 pairs of same-sex fraternal twins (283 male and 566 female pairs), we found that females have a strong genetic influence and zero shared-environmental influences on their tendency to become entrepreneurs. In contrast, males show zero genetic influence, but a large shared-environmental influence... such individuals appear to be 'both born and made'."

The difference in gender also make clear the notion that genes influence females and males differently, but they still eventually reach the same conclusion on their journey. As with everything, we still do not know enough about our genes to get conclusive, definite answers, and, even then, never forget environmental effects could re-direct people in a variety of ways.

How much start-up capital are you able to attain? How dedicated is your work force to your vision so that make it a success? How well-received are you not only by the market but by the influential people who rely on to believe in your brand as well?

And those are just a few factors...

Studies like the ones above do show how genetics are becoming more important than ever before when it comes to our understanding of the world. It's not only about predisposition to disease, ancestry, and race.

We are becoming more and more capable of harnessing the power of genetics and applying it to our daily lives, and there is an opportunity to make South Africa the best environment for entrepreneurship in the world. Take the example of other great startup cities, such as Lisbon. In Lisbon, they went to great lengths to provide great access to capital, human resource, and cut red-tape for new businesses. Now, Lisbon is one of the top startup cities in the world - nominated European Capital of Entrepreneurship in 2015.

In South Africa, we have the ability to follow Lisbon, and go even further. With a talented, ambitious, and abundant workforce, great access to high quality office space and a low cost of living, we have everything the country needs to be the next Silicon Valley. Coupled with our incredible quality of life (and weather!), it seems to me that for all South Africans, this a time where nothing should be holding you back.

It's inspirational to think that our entrepreneurial fire has only been started, and we as a country should do everything we can to foster an environment supportive of entrepreneurship and startup culture for everybody no matter how or where they were born. With this approach, we can make South Africa a world leader in both our genetic talent pool, and our fostering environment for entrepreneurship.

See the rest here:
Entrepreneurship Is Genetic, And South Africa Is The Ideal Environment For Young Entrepreneurs To Thrive - Huffington Post South Africa (blog)

WSU forms ask non-inclusive race and gender questions, even though these answers are not important to the evaluation of the form.

While our country has become increasingly more accepting of individuality, there are still many instances where our society is failing to adequately represent minorities.

For example, the WSU Junior Writing Portfolios (JWP) cover sheet asks students to specify their gender as either male or female, giving no option for individuals who do not identify as one or the other.

Freshman mechanical engineering major Nicklaus McHendry said that they have had difficulties with how to identify themself for others.

Ive been out as a non-binary person for many years, McHendry said. At this point (it is exhausting to see) a question with a binary male or female box on a form that I dont particularly feel I need to be asked that on.

So, why is WSU asking questions such as these on forms where specifying something such as gender or race isnt necessary? For the JWP, WSU just wants a representation of a students writing ability.

I dont feel that my gender or anyone elses should be specified on a form that doesnt have anything to do with it, McHendry said.

The director of writing assessments, Xyanthe Neider, wrote in an email that students can mark the gender that they feel most adequately represents them or they can leave the question blank.

We understand that gender is much more fluid beyond the binary male/female designators and we revisit this regularly, Neider wrote.

However, there is no indication on the form to suggest that specifying ones gender is optional.

Consequently, attempting to answer this question has left many students confused and frustrated while they ponder which of the two boxes most correctly identifies them.

Its hard not to be upset, McHendry said. In order to get through the day and not spend every waking moment of my life being bothered, angry and upset ... I try to focus on things that are more important.

If they want to ask about gender, they should add the option to write it in on the JWP form, which would make certain minority students feel more accepted.

In addition to the JWP, the WSU online application for admission requires students to report their gender as either male or female. The application also asks students to report their race.

Many universities across the country consider ethnicity and gender in the admission process, which unfairly puts some students at a disadvantage and gives others the upper hand.

According to ballotpedia.org, Washington is one of eight states that currently bans public universities from considering race in admissions, a policy known as Affirmative Action.

WSU does not discriminate on the basis of race, sex, sexual orientation, gender identity/expression (or) religion, the Office for Equal Opportunity states on its website.

It is completely inappropriate to ask students to specify certain personal demographics when those responses have absolutely nothing to do with the reason the form is completed.

So, if WSU is not allowed to consider race during the application process, then why are they asking students to specify it on their application?

Emily Hogan is a freshman genetics and cell biology major from Harrington, Delaware. She can be contacted at 335-2290 or byopinion@dailyevergreen.com. The opinions expressed in this column are not necessarily those of the staff of The Daily Evergreen or those of The Office of Student Media.

Read the original:
Binary thought suppresses identity - The Daily Evergreen

In a recent article, a doctor in China has identified a man who has 44 chromosomes instead of the usual 46. Except for his different number of chromosomes, this man is perfectly normal in every measurable way.

His chromosomes are arranged in a stable way that could be passed on if he met a nice girl who had 44 chromosomes too. And this would certainly be possible in the future given his family history.

But why doesn't he have any problems? A loss of one let alone two chromosomes is almost always fatal because so many essential genes are lost.

In this case, he has fewer chromosomes but is actually missing very few genes. Instead, he has two chromosomes stuck to two other chromosomes. More specifically, both his chromosome 14's are stuck to his chromosome 15's.

So he has almost all the same genes as any other person. He just has them packaged a bit differently.

This is an important finding because it tells us about a key genetic event in human prehistory. All the evidence points to humans, like their relatives the chimpanzees, having 48 chromosomes a million or so years ago. Nowadays most humans have 46.

What happened to this 44 chromosome man shows one way that the first step in this sort of change might have happened in our past. Scientists could certainly predict something like this. But now there is proof that it can actually happen.

Note added in Proof: Here are some older papers that I missed that have very similar findings:

And the current one:

Case Report: Potential Speciation in Humans Involving Robertsonian Translocations.

His Story

So how did this man end up with 44 chromosomes? It is a story of close relatives having children together. And a chromosomal rearrangement called a balanced translocation.

A balanced translocation is when one chromosome sticks to another. Because no genes are lost in this process, it usually doesn't have any effect. Until these folks try to have kids that is.

Usually around 2/3 of pregnancies involving one person with a balanced translocation will end in miscarriage. This has to do with how chromosomes separate when eggs and sperm are made. This process is called meiosis.

Remember, humans (and most other living things) have two copies of each chromosome. So they have two copies of chromosome 1, two copies of chromosome 2, etc. Only one chromosome from each pair gets put into any one sperm or egg. That way, when the sperm fertilizes the egg, the fetus has the right number of chromosomes.

This is where the problem starts for people with a balanced translocation. They have one unpaired chromosome and a pair with an extra chromosome. Here is what can happen in this situation:

The top row represents two potential parents. The parent on the right has a balanced translocation. There are two possible ways for the fused chromosome to line up.

In the figure, only two chromosomes are shown. Numbers 14 and 15 were chosen because these are the two that are fused in the 44 chromosome man.

The parent with the balanced translocation can make 4 different kinds of sperm or egg (the second row). As the figure shows, when the eggs and sperm combine, 1/2 of the time the fetus ends up with an extra or missing chromosome. Unless this chromosome is the X, Y or number 21, the usual result is miscarriage or being born with severe problems.

In this case it would almost certainly result in miscarriage. In fact, the 44 chromosome man's family has a long history of miscarriages and spontaneous abortions.

To get two of the same balanced translocations, both parents need to have the same balanced translocation. This is incredibly rare. Except when the parents are related.

In this case, both parents are first cousins and they share the same translocation. When these parents try to have kids, they run into the same kinds of problems that can happen with one balanced translocation. Except that the problems are doubled. This makes for the many possibilities outlined below:

This very complicated table shows the 36 possible outcomes when two parents with the same balanced translocation attempt to have a child.

In this representation, the father's possible sperm are shown on the top and the mother's eggs on the side. Each pregnancy has only an 8 in 36 chance for success. And 1 out of 36 would have two of the same balanced translocation (the circled possibility).

Theoretically the 44 chromosome man should have fewer problems having children than his parents did. As this figure shows, there are no unpaired chromosomes when he and a woman with 46 chromosomes have children. But all of their kids would have a balanced translocation:

So this is how he came to have 44 chromosomes. This might also be how humans started on the road to 46 chromosomes a million or so years ago.

See the article here:
The 44 Chromosome Man | Understanding Genetics