GABRA2 has been studied across a range of the phenotypes discussed above. Subsequent studies in the COGA sample gave evidence that GABRA2 variation is associated with other SUDs79,80, antisocial personality disorder77 and conduct disorder80, suggesting that GABRA2 is involved in the predisposition to alcohol dependence through a general externalizing-disorder pathway. The same GABRA2 SNPs originally associated with alcohol dependence in a wide age range of adults also predict early conduct problems (rather than the diagnosis of dependence) in a very young adult sample80. Here too, the effects of GABRA2 variants are moderated by environmental variables, as high levels of parental monitoring diminish the association with conduct disorder81.
