Abstract
BACKGROUND: Recent studies of the genetics of alcoholism have focused on a cluster of genes encoding for gamma-aminobutyric acid (GABA(A)) receptor subunits, which is thought to play a role in the expression of addiction phenotypes. This study examined allelic associations between 2 single nucleotide polymorphisms (SNPs) of the GABRG1 gene (rs1391166 and rs1497571) and alcohol phenotypes, namely level of response to alcohol, alcohol use patterns, and alcohol-related problems. METHOD: Participants were non-treatment-seeking seeking hazardous drinkers (n = 124) who provided DNA samples, participated in a face-to-face interview for level of response to alcohol, and completed a series of drinking and individual differences measures. RESULTS: Analyses revealed that a SNP of the GABRG1 gene (rs1497571) was associated with level of response to alcohol and drinking patterns in this subclinical sample. Follow-up mediational analyses were also conducted to examine putative mechanisms underlying these associations. DISCUSSION: These findings replicate and extend recent research suggesting that genetic variation at the GABRG1 locus may underlie the expression of alcohol phenotypes, including level of response to alcohol.