title: The GNB3 C825T polymorphism and depression among subjects with alcohol dependence.
abstract: The T allele of the C825T polymorphism in the G-protein beta(3) subunit gene (GNB3) is related to the increase of signal transduction by the G-protein. G-proteins are intermediary paths in signal transduction from receptors involved in mood regulation and substance dependence. We studied the C825T polymorphism in individuals with (i) alcohol and nicotine dependence (n = 109), (ii) nicotine dependence only (n = 117) and (iii) non-dependent controls (n = 108). We also tested for possible associations with psychiatric comorbidities among alcohol-dependent individuals. No differences were detected for allele and genotype frequencies in individuals with or without dependencies. Alcohol-dependent individuals with the heterozygous genotype presented more frequently major depressive disorder (chi(2) = 12.34; p = 0.002). These findings, taken together with other studies suggesting an influence of the C825T polymorphism in major depressive disorder, support the hypothesis of the involvement of G-proteins in mood regulation.
authors.affiliation: Department of Genetics, Institute of Biosciences, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil.
authors.forename: A P
authors.initials: AP
authors.lastname: Prestes
authors.forename: F Z C
authors.initials: FZ
authors.lastname: Marques
authors.forename: M H
authors.initials: MH
authors.lastname: Hutz
authors.forename: C H D
authors.initials: CH
authors.lastname: Bau
mesh_terms: D000437:Alcoholism / Q000150:complications* / Q000235:genetics; D003863:Depression / Q000150:complications* / Q000235:genetics*; D020962:Heterotrimeric GTP-Binding Proteins / Q000235:genetics*; D006801:Humans; D008297:Male; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D014029:Tobacco Use Disorder / Q000150:complications / Q000235:genetics
chemical_list: C454420:G-protein beta3 subunit; D020962:Heterotrimeric GTP-Binding Proteins