Association analysis of the GABA(A) receptor subunit genes cluster on 5q33-34 and alcohol dependence in a Japanese population

Recent investigations suggest that genetic susceptibility to alcohol dependence may be conferred by GABA(A) receptor subunit genes. In this study, three RFLPs at the GABA(A)β2, GABA(A)α6, GABA(A)α1 and two at the GABA(A)γ2 receptor subunit genes, were examined for association with alcohol dependence in 189 subjects meeting DSM-III-R criteria for this disorder and 152 unrelated controls from a Japanese population. The results demonstrated no association between the AlwNI RFLP at the GABA(A)α6 receptor subunit gene and alcohol dependence (P = 0.059). However, the NciI RFLP at the GABA(A)γ2 receptor subunit gene was associated with alcohol dependence comorbid with antisocial personality disorder (P = 0.021). This supports a recent finding reporting an association between the GABA(A)γ2 receptor subunit gene and alcohol dependence with criminal record in a Finnish population. Taking into account the effects of multiple comparisons, this result should be interpreted with caution pending replication.