Although severe stress, such as sexual abuse, early in life has been shown to increase the risk of alcohol and drug addiction later on, scientists have found that some abuse survivors carry a genetic variation that protects them from the increased risk of alcohol abuse and its effects.

Researchers at the Washington University School of Medicine in St. Louis identified the key set of genetic variations, called the H2 haplotype, in a recent study. They believe that the finding could support the development of targeted treatments for alcohol dependence that are based on both genetic traits and history of exposure to severe stress. Scientists estimate that genetics account for about half the risk of developing alcoholism, while the other half comes from environmental factors.

Elliot C. Nelson, M.D., lead author of the study, commented: "We looked at how genes and environment interact. Our analysis included both sexual abuse and information about the DNA region that carries the H2 haplotype. People who carry that genetic pattern were protected against the risks for alcohol consumption and alcohol dependence typically associated with sexual abuse."

The researchers found that sexual abuse survivors with the alternate genetic pattern, known as the H1 haplotype, were three times more likely than study participants who had not been abused to be heavy drinkers and alcohol dependent. By contrast, participants with the H2 haplotype appeared to be completely protected from this increased risk.

(Source: sciencedaily.com)

Labels: genetics, sexual abuse, substance abuse