observed; the probability of nicotine dependence remained high and relatively constant across numbers of smoking peers among those with the AA genotype. To explore these divergent findings we estimated models including both the parent monitoring scale and H.S. peer smoking, which did not significantly alter either measures’ main effect association with nicotine dependence, nor did parent monitoring change the interaction between peer smoking and rs16969968 results (available upon request). Additionally, there was no statistical interaction between H.S. peer smoking and parent monitoring in predicting nicotine dependence (p = 0.36), nor was there evidence of three-way interaction between rs16969968, parent monitoring, and peer smoking (p = 0.50). Thus our prior findings for rs16969968 with parent monitoring and those in the current study of peer smoking appear to be independent: increases in number of peers who smoke does not appear to be the mechanism by which low parent monitoring increases the expression of genetic risk associated with rs16969968.
