implications of these findings for the present study are intriguing. Adolescent carriers of the G allele may be prone to affiliating with deviant peers in part due to their heightened sensitivities to social reward and to fear of social rejection. These liabilities may in turn increase susceptibility to peer influences on initiation of drinking and escalation to problematic use. This possibility is purely speculative at this time, however, and warrants empirical testing in future research.