DRD3 Gene rs6280 Polymorphism May Be Associated with Alcohol Dependence Overall and with Lesch Type I Alcohol Dependence in Koreans

Abstract

Background: Several polymorphisnns of the dopamine D-3 receptor (DRD3) gene are reported to be involved in the susceptibility to alcoholism. Although the DRD3 rs6280 (Ser9-Gly) polymorphism plays an important role in various psychiatric disorders, findings regarding the association between this single-nucleotide polymorphism (SNP) and alcohol dependence (AD) have been inconsistent. Therefore, the present study investigated the association between the DRD3 gene rs6280 polymorphism with AD and Lesch type I AD in Korean subjects. Methods: The DRD3 rs6280 SNP was genotyped in a case-control sample comprising 245 AD patients and 130 healthy controls (HCs). Alcohol Use Disorders Identification Test (AUDIT) scores were also compared relative to genotype in all of the participants. Results: This SNP was significantly associated with both AD overall (chi(2) = 10.09 and p = 0.001, and chi(2) = 10.60 and p = 0.005, for the recessive and additive models, respectively) and with Lesch type I AD (chi(2) = 11.70 and p(r) = 0.001, and chi(2) = 11.70 and p = 0.003, for the recessive and additive models, respectively). The allele frequency differed significantly (chi(2) = 8.45, p = 0.004) between Lesch type I AD and HC subjects. The AUDIT total (F = 6.56, p = 0.011), hazardous alcohol use (F = 7.12, p = 0.008), dependence symptoms (F = 5.10, p = 0.025), and harmful alcohol use (F = 4.83, p = 0.029) scores were significantly higher in those who did not possess the S allele (genotype GG) than in those who did (genotypes SS +/- SG). Conclusions: The findings of this study suggest that the DRD3 rs6280 polymorphism is associated with the development of both AD overall and Lesch type I AD in Koreans. (C) 2014 S. Karger AG, Basel