This study extends the literature by testing the effects of the A118G SNP of the OPRM1 gene on subjective response to alcohol in a sample of non-treatment seeking alcohol dependent individuals. Participants were prospectively genotyped for the OPRM1 gene and clinically ascertained for current alcohol dependence status. Participants completed two randomized infusion sessions, one in which they received alcohol (target BAC = 0.06 g/dl) and one in which they received a saline control. It was hypothesized that G-allele carriers would display greater sensitivity to the stimulant and reinforcing effects of alcohol, as compared to saline, consistent with the role for the polymorphism in alcohol-induced reward. A secondary aim of this study was to examine the relationship between alcoholism severity and subjective response to alcohol. Given that the vast majority of alcohol administration studies to date have been conducted on heavy drinkers or at-risk samples, it was clinically relevant to ascertain how alcoholism severity is related to the subjective experience of alcohol. Consistent with the literature on the neurobiology of AD(Koob, 2003; Koob and Le Moal, 2008; Robinson and Berridge, 2001), it was hypothesized that individuals at earlier stages of alcoholism would report stronger positiveand stimulant effects.
