Kendler, Gardner, and Dick (in press) found additional evidence for significant GxE on alcohol consumption among adult male twins from Virginia based on retrospective reports of adolescent environmental exposures. Alcohol availability, peer group deviance, and low prosocial behaviors (e.g., low levels of participation in organized sports and community activities) moderated genetic risk for AUDs and non-specific externalizing disorders during early and mid-adolescence, such that genetic influences were greater in less restrictive environments with easier access to alcohol. There was little evidence for GxE for three other measures of environmental exposure or during later adolescence (after age 17).
