A nonsynonymous SNP rs1799971 of OPRM1 (chromosome6q25.2) relates to IV alcohol subjective effects and cue reactivity from alcohol (Courtney et al., 2015; Ray et al., 2012; Ray and Hutchison, 2004), and might be associated with both decreased receptor glycosylation and half-life (Weerts et al., 2017). G-allele carriers of rs1799971 exhibit decreased mu opioid receptor binding compared to those with AA genotypes (Weerts et al., 2013), and the former may relate to increased responses to oral and IV alcohol and on a retrospective questionnaire, as well as lower AUD risks (Ehlers et al., 2008; Ray and Hutchison 2004; Schwantes-An et al., 2016). The same SNP might relate alcohol dependence risks and higher alcohol self-administration (Hendershot et al., 2014; Otto et al., 2017; van der Zwaluw et al., 2007, 2009). C- allele carriers of a SNP in linkage disequilibrium (LD) with rs179971, rs3778150, demonstrate decreased intensities of response to oral alcohol. (Hancock et al., 2015; Otto et al., 2017).
