Prestes A P, Marques F Z C, Hutz M H, Bau C H D
Department of Genetics, Institute of Biosciences, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil.
J Neural Transm (Vienna). 2007;114(4):469-72. doi: 10.1007/s00702-006-0550-2. Epub 2006 Aug 8.
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.
G蛋白β(3)亚基基因（GNB3）中C825T多态性的T等位基因与G蛋白信号转导的增强有关。G蛋白是参与情绪调节和物质依赖的受体信号转导的中间途径。我们研究了以下个体的C825T多态性：（i）酒精和尼古丁依赖者（n = 109），（ii）仅尼古丁依赖者（n = 117）和（iii）非依赖对照组（n = 108）。我们还测试了酒精依赖个体中与精神共病的可能关联。在有或没有依赖的个体中，未检测到等位基因和基因型频率的差异。具有杂合基因型的酒精依赖个体更常出现重度抑郁症（χ(2)= 12.34；p = 0.002）。这些发现与其他表明C825T多态性对重度抑郁症有影响的研究一起，支持了G蛋白参与情绪调节的假说。
