Gene variation makes alcoholism less likely in some survivors of sexual abuse

Exposure to severe stress early in life increases the risk of alcohol and drug addiction. Yet surprisingly, some adults sexually abused as children — and therefore at high risk for alcohol problems — carry gene variants that protect them from heavy drinking and its effects, according to researchers at Washington University School of Medicine in St. Louis.

The researchers, from the university’s Midwest Alcoholism Research Center, say the finding could aid the development of therapies for alcohol dependence by offering suggestions for targeted treatments based on genetic traits and history of exposure to severe stressors.

Scientists estimate that about half the risk for alcoholism is encoded in a person’s genes. The rest comes from environmental factors, such as age at first drink and exposure to extreme stress. Other research has suggested that when the environmental risk factors occur during key periods of brain development, genes and environment working together can increase the likelihood an individual will become alcohol dependent. Child sexual abuse is one of the environmental stressors that can interact with genes to significantly increase the risk for alcohol problems.