Fourth, previous studies of gene-environment interaction in alcohol intake or problems have focused on reduced social control or increased psychosocial adversity (42, 43). Here we asked a different question—whether individuals at high familial risk for alcohol use disorder had a different sensitivity to the protective effects of marriage than those without such risk. As expected, we found a substantial main effect of those with a positive family history having a stronger risk for alcohol use disorder. More interestingly, we found robust evidence that the protective effects of marriage were stronger in those with a family history compared to those without. This effect is consistent with recent findings that severe problem drinkers show the greatest decrease in drinking after the transition to marriage (28). Those at highest risk for alcohol problems appear to be the most likely to benefit from the protective effects of marriage.
