Association between Ser311Cys polymorphism in the dopamine D2 receptor gene and schizophrenia risk: a meta-analysis in Asian populations.

Numerous studies have evaluated the association between Ser311Cys (rs1801028, C>G) polymorphism of the dopamine D2 receptor (DRD2) gene and schizophrenia risk. However, the specific association is still controversial. We examined whether DRD2 Ser311Cys polymorphism confers schizophrenia risk in Asian populations. Sixteen studies were retrieved reporting on a total of 2268 schizophrenia patients and 2423 healthy controls. Meta-analysis of the results showed significant associations between Ser311Cys polymorphism and schizophrenia risk in the comparisons of G versus C (odds ratio (OR) = 1.47, 95% confidence interval (CI) = 1.18-1.83, P = 0.0006) and CG+GG versus CC (OR = 1.45, 95%CI = 1.16- 1.82, P = 0.001). In a subgroup analysis by nationality, we found a significant association between Ser311Cys polymorphism and schizophrenia risk in the comparisons of G versus C and CG+GG versus CC genotype in the Japanese population (OR = 1.75, 95%CI = 1.30-2.35, P = 0.0002; OR = 1.72, 95%CI = 1.27-2.33, P = 0.0004; respectively) but not in Chinese and Indian populations. In conclusion, the G allele of DRD2 Ser311Cys polymorphism involves a potential risk factor for schizophrenia in Asian populations, especially in the Japanese population.