Association analysis of a functional G protein beta3 subunit gene polymorphism (C825T) in mood disorders

The guanine nucleotide-binding proteins (G proteins), heterotrimers consisting of alpha, beta and gamma subunits, convey signals initiated by the activation of many neurotransmitter receptors. Evidence for involvement of the G proteins in mood disorders relies on the effects of mood stabilizers and antidepressants on G protein function. In addition, abnormalities in the expression of G proteins have been demonstrated in mood disorder patients. Therefore, we tested the hypothesis that a functional polymorphism (C825T) in the G protein beta3 gene subunit (GNB3) confers susceptibility to mood disorders. A population-based association study was utilized, and GNB3 was genotyped for 144 mood disorder patients and 153 normal controls. The results reveal that it is not likely that the C825T polymorphism in the GNB3 gene subunit is involved in mood disorder pathogenesis. Further studies of the associations between other G protein subunits and mood disorder are needed to fully elaborate the involvement of this protein in mood disorders.