Polygenic scores derived from variants associated with consumption are predictive of use, misuse and problems among young adults. As hypothesized, being in a romantic relationship moderated the association between GPS and each alcohol phenotype (drinking frequency, intoxication frequency and AD symptoms). Similar to previous twin research [34,35], among individuals with elevated genetic predisposition levels of misuse were lower in those in a romantic partnership. We posit that the constraints and responsibilities placed on individuals within romantic partnerships limits their ability to express underlying predispositions towards alcohol misuse, fitting with the social control model of gene–environment interaction[5,23]. Additional inspection (Supporting information, Fig. S1) revealed that these interactions did not appear to be driven by outliers at either end of the distribution.
