Addiction Research

Substance Using Peers Increases Genetic Likelihood to Abuse

Many parents throughout the world cringe when their children make friends with individuals who make choices outside of the belief of the parents. Such choices often include drugs and alcohol and can influence activities in other children.

New research featured in a recent Science Daily release takes the study into drug use beyond genes and environment and looks at other factors. For instance, a young woman with a genetic-based predisposition to substance use is also predisposed to select friends who smoke, drink or use drugs. As a result, her environment is altered to encourage substance use.

In addition, this exposure to friends who also use substances increases her genetic inclination to use drugs regularly. As a result, her already increased likelihood for substance use is increased even more.

Washington University researchers examined a sample of more than 2,000 female twins, looking for links between women who regularly used tobacco, alcohol and drugs and women whose friends were involved in the use of alcohol, cigarettes and cannabis. The researchers found links between genetic vulnerability to regular use and the increased likelihood to use as a result of exposure to a certain set of friends who use.

While we often select peers with similar interests, this study highlighted that heritable influences on an individual’s own regular substance use increased as they affiliated with more drug-using peers. Increased affiliations are directly correlated with a more ‘genetic’ form of regular substance use.