Given the clear influence of delinquent peers upon externalizing behavior (i.e., peer socialization model), and the evidence for the association of GABRA2 with increased susceptibility to social contexts, we prospectively investigated the moderating role of GABRA2 genetic variation on the influence of peer delinquency on externalizing behavior among adolescents from the Michigan Longitudinal Study (MLS), a sample enriched with adolescents at risk to develop problem behavior, an important feature to detect small genetic effects. Specifically, we tested whether GABRA2 risk variants increase the degree of susceptibility to delinquent peers on externalizing behavior and its subscales, rule breaking and aggression.
