other like-mind peers, making other children with similar externalizing tendencies more likely to want to spend time with them. Taken together, our results demonstrate that genetic risk conferred not only direct effects on adolescent externalizing behavior but also impacted subsequent externalizing behavior indirectly through perceived peer substance use. This underscores the importance of gene-environment interplay, and highlights gene-environment correlations, particularly in relation to peers, as important mechanisms by which genetic risk influence behavior and psychosocial outcomes in adolescence. Additional research is needed to consider other psychosocial mechanisms underlying genetic risk for adolescent outcomes.
