was comprised of high-risk adult alcohol users, the majority of whom may have established their drinking patterns and thus genetic influences on their alcohol use may be more stable. Future research is needed to further examine developmental changes in polygenic effects on alcohol use. However, the role of social support on alcohol use varied across adulthood. Specifically, friend support was associated with more alcohol use in emerging adulthood, but was protective and associated with lower alcohol use in young and middle adulthood. This may be because alcohol use during emerging adulthood typically occurs in peer social settings (LaBrie et al., 2007). Thus, it is possible that support from friends during emerging adulthood may not provide increased social control in limiting alcohol use. Family support was most protective against alcohol use in emerging adulthood, but was associated with more alcohol use in young adulthood. This finding is consistent with prior research showing the continued protective role of parental support for emerging adults (Kouros et al., 2017; Serido et al., 2014). Young adults may be more likely to drink with family members (e.g., spouse) and thus a strong family support may be associated with more drinking in the family context during young
