as additional predictors to the regression model (Model 3). We also examined potential gene-environment correlations (rGE) by testing correlations between alc-PRS and family/friend support. Significant rGE were accounted for in our models testing G×E effects by specifying alc-PRS and family/friend support to be correlated using the “WITH” command in Mplus. To check the robustness of significant G×E effects, we conducted additional analysis that included alc-PRS × covariate as well as social support × covariate interaction terms in the regression model to further account for potential confounding effects, following recommendations by Keller (2014).
