Published: Thursday, March 14, 2013 at 5:13 p.m. Last Modified: Thursday, March 14, 2013 at 5:13 p.m.

That some people are genetically prone to addictions is nothing new, but some scientists have expressed surprise at the degree of addictive tendencies.

For example, if you have a high-risk genotype for marijuana addiction, and also suffer from neuroticism or anxiety, you have an eight- to nine-fold risk of becoming addicted to marijuana.

What's more, in utero exposure to the drug might induce long-term addictive tendencies -- at least in rats.

Professor Yasmin Hurd, a neuroscientist and professor of psychiatry at the Ichan School of Medicine in Mount Sinai, N.Y., cited these examples Thursday in a talk titled "The Vulnerable Brain: Understanding the Neurobiology of Addiction Risk." Her talk was one of two expert lectures delivered Thursday at the McKnight Brain Institute as part of brain awareness week, a global campaign to raise awareness of the brain.

Early addiction research in neuroscience focused on dopamine dependence -- the "feel-good" chemical released abundantly in the brain during drug usage. The flip side of this immediate surge is a long-term lessening of dopamine actually produced by the brain, which over time, decreases a person's ability to experience pleasure.

But scientists realized addiction in the brain was "much more complicated" than decoding dopamine circuitry, so they began looking at genetic mutations that might play a role.

"Clearly there is not one gene that makes someone a heroin abuser," Hurd said, adding, "Genetics has an important for understanding the vulnerability of heroin abusers."

Hurd noted that marijuana is the most widely abused drug in the U.S., while heroin and cocaine are the most addictive. Heroin overdose has the highest mortality rates of any drug.

One issue that interests Hurd is the effect of marijuana use by pregnant women on their babies. The scientists found that men were more vulnerable to addictions than women. Other studies have shown that people -- especially men -- with certain behavioral traits such as anxiety, when combined with a genetic vulnerability to addiction, or a mother who smoked in utero, were especially at risk.

See original here:
Professor: Genetic mutations can amplify drug addictions

Comments are closed.