Ethnic-specific meta-analyses of association between the OPRM1 A118G polymorphism and alcohol dependence among Asians and Caucasians.

Abstract

Many studies have investigated the association between the OPRM1 A118G polymorphism (rs1799971) and alcohol dependence, but the results were inconsistent. To better understand this relationship, ethnicity-specific meta-analyses were conducted. We retrieved all eligible studies published up to April 12, 2011 from the PubMed/MEDLINE, EMBASE, and ISI Web of Science databases. Ethnicity-specific meta-analyses were performed using either fixed- or random-effect models as appropriate. Twelve independent studies with 1900 cases and 2382 controls were included. Five studies were conducted in Asians and seven in Caucasians. Ethnicity-specific meta-analyses revealed that the A118G polymorphism was significantly associated with alcohol dependence risk in Asians (GA vs. AA: odds ratio [OR], 1.73; 95% confidence interval [CI], 1.33-2.25; GA+GG vs. AA: OR, 1.57; 95% CI, 1.22-2.02), but not in Caucasians (GA vs. AA: OR, 1.05; 95% CI, 0.75-1.49; GA+GG vs. AA: OR, 1.11; 95% CI, 0.79-1.55). The OPRM1 A118G polymorphism may contribute to the susceptibility of alcohol dependence in Asians but not in Caucasians.