The overarching goal of this study was to examine the interactive effects between genetic risk and social support in relation to alcohol use among EA and AA adults, using a genome-wide polygenic risk score approach. Utilizing data from a large diverse sample of adults from extended families enriched for alcohol use disorders, our findings indicated that perceived social support from friends buffers the effect of genetic risk for alcohol use on phenotypic alcohol use among both EA and AA (middle adulthood only for AAs) adults. We found no significant difference in the role of alc-PRS and social support in relation to alcohol use between males and females; however, important developmental differences in the role of social support in relation to alcohol use were observed among both EAs and AAs. This study extends the literature by taking a polygenic score approach to examine developmental G×E effects among both EA and AA adults, contributing novel insights regarding interactions between polygenic risk and social support in relation to alcohol use across ancestral groups, developmental stages, and sex.
