Our results indicate that individuals with 1 or 2 copies of the more common SNP4 C-allele, SNP5 A-allele, or SNP6 T-allele experience a greater initial response after their BrAC rises to the target level of 50 mg%. It is possible that, because of these greater initial subjective responses, such individuals may be less likely to continue drinking. On the other hand, individuals homozygous for the alcohol dependence–associated A allele at SNP4, the G allele at SNP5, or the C allele at SNP6 experience a lower initial response after their BrAC rises. Thus, these individuals may need to drink more alcohol to achieve a comparable level of alcohol-induced subjective response and may be more likely to drink if given access to alcohol. However, studies are needed to determine the effects of GABRA2 alleles on drinking behavior as it occurs in natural settings or using self-administration paradigms.
