Consistent with previous findings, the strongest evidence for GABRA2 SNP effects was with quantitative alcohol dependence variables, namely the number of DSM-IV criteria met for alcohol dependence (sumAD4) and the principal component factor score extracted from the DSM-IV alcohol dependence criteria variable (factAD4). Five SNPs, four of which are located within the major LD block that extends from intron 3 to the 3'UTR of GABRA2 in our sample, were nominally associated (p < 0.05, “within” test of association) with these two phenotypes. The fact that this result is not significant after correction for multiple testing, combined with the non-significant finding for these markers for the “total” test of association, means that the effect of these markers on quantitative alcohol dependence variables is modest at best.
