The impact of gene-environment interaction on alcohol use disorders.

This article describes three types of gene-environment interactions and the challenges inherent in interpreting these interactions. It also reports on what is known about gene-environment interactions in the field of alcohol use disorders (AUDs). Twin studies of the interaction of genetic and environmental influences on AUDs have resulted in relatively consistent findings and have suggested general mechanisms for interaction effects. These studies generally find that environments that exert more social control (e.g., higher parental monitoring, less migratory neighborhoods, etc.) tend to reduce genetic influences, whereas other environments allow greater opportunity to express genetic predispositions, such as those characterized by more deviant peers and greater alcohol availability. Conversely, the gene-environment literature that has been developed surrounding specific genes has focused largely on the role of stress as a moderator of genetic effects.