the G allele for both SNPs analyzed in this study, has been associated with alcohol dependence in four studies 5, 6, 8, 9 and with the complementary haplotype (the A allele from both SNPs) in three studies 3, 11, 12. The studies from Edenberg 6 and Agrawal 3 used the same data set from the Collaborative Study on the Genetics of Alcoholism (COGA) where Agrawal reported the A allele for both SNPs rs279858 and rs279826 associated with comorbid illicit drug dependence, while Edenberg later clarified that the G-allele-containing haplotype was associated with alcohol dependence 50. When the SNP rs279858 was compared to the efficacy of three psychosocial treatments, different drinking outcomes among treatments were observed for subjects with the A allele, while no difference in outcome among treatments was observed for G allele carriers 4. The authors suggested that an elevated anxiety level driven by the presence of the G allele may compromise the outcome as a result of enhanced stress and impulsivity. Individuals with the G allele may need to drink more alcohol to achieve the desired effects compared to AA subjects who experienced a higher subjective response to alcohol 4. One11 of the three studies that reported the
