−141 C insertion/deletion polymorphism of the dopamine D 2 receptor gene is associated with schizophrenia in C hinese H an population: Evidence from an ethnic group‐specific meta‐analysis

Accumulate evidence has implicated dopamine D 2 receptor gene polymorphisms in the etiology of schizophrenia. A single nucleotide polymorphism, −141 C insertion/deletion ( I ns/ D el) (rs1799732), in the promoter region of the dopamine D 2 receptor gene has been linked to schizophrenia; however, the data are inconclusive. This study investigated whether the −141 C polymorphism is associated with the risk of schizophrenia in different ethnic groups by performing a meta‐analysis. A total of 24 case–control studies examining the association between −141 C I ns/ D el polymorphism and schizophrenia were identified according to established inclusion criteria. Significant association was revealed between −141 C I ns/ D el polymorphism and schizophrenia risk in dominant genetic model ( I ns/ I ns +  I ns/ D el versus D el/ D el) (odds ratio = 0.33, 95% confidence interval = 0.14–0.81, z = 2.41, P  = 0.02) in C hinese H an but not in C aucasian, J apanese or I ndia populations. Our results indicate that −141 C I ns/ D el polymorphism might be a susceptibility factor for schizophrenia in C hinese H an population.