age were included as covariates. Preliminary analyses indicated only a modest association between relationship status and intoxication frequency (r = −.10), and no association between the GW- and DHS-scores and relationship status (range rpb = −0.04 to 0.004, all p > 0.14). The latter null associations, in particular, minimized concerns about gene-environment correlation as a potential confounder when testing G×E effects. Regarding multiple testing concerns, we note that the inferential test of interest for this research question was a chi-square test of the proportion of DHS SNPs among the set of SNPs with a significant (p < .05) G×E effects relative to the overall proportion of DHS SNPs, thus representing a single statistical test for enrichment.
