higher alcohol sales15, presumably through easier access for those with a predisposition. In fact, many of the environments that reduce genetic influences on substance use seem to operate through social control. Environments that are more controlling and provide greater social structure reduce the impact of genetic risk for SUD. For example, religiosity seems to moderate genetic influences on alcohol use, with genetic factors playing a reduced role among individuals with a religious upbringing16. A similar effect has been reported for smoking, whereby high religiosity attenuates genetic effects on initiation of tobacco use17. The importance of genetic influences on adolescent alcohol use is reduced in rural settings and neighborhoods with less migration and presumably increased stability (which likely leads to enhanced community monitoring of adolescent behavior)15. Genetic influences on adolescent smoking are attenuated under conditions of higher parental monitoring18 (Fig. 3). Greater control and structure, at the levels of legislative restrictions, social institutions such as religion, interpersonal relationships (for adults), parenting (for adolescents) and neighborhoods, can all reduce the importance of individual genetic predispositions toward substance use.
