account for any effects of rs3778150 (Schwantes-An et al., 2016). Although the direction of effect for the associated allele is consistent across these two studies, previous findings implicating rs1799971 in alcohol sensitivity and alcohol use may have inadvertently been capturing the effects of rs3778150 and likely other OPRM1 intron 1 variants, as has been suggested in past research (Zhang et al., 2006; Levran et al., 2011). As such, rs3778150 may account, at least in part, for the mixed relations previously observed for rs1799971 and alcohol use phenotypes.
