RGS4 polymorphisms and risk of schizophrenia: an association study in Han Chinese plus meta-analysis

Recently, several researches based on expression analysis, genetic linkage and association studies have suggested that the regulator of G-protein signaling 4 (RGS4) might be a schizophrenia susceptibility gene. However, these linkage and association studies have been conducted using different ethnic samples, and have therefore tended to produce inconsistent results. To help to clarify this inconsistency, we used non-family based samples to carry out a case-control analysis on six single nucleotide polymorphisms (SNPs) (including four widely investigated SNPs, SNP1, 4, 7, 18 and another two SNPs, rs2842030 and rs2344671) in a Chinese Han sample set comprising 288 schizophrenia patients and 288 normal controls. All genotypings were conducted by direct sequencing and all SNPs were in Hardy-Weinberg equilibrium. We found no individual SNPs or haplotypes to be associated with schizophrenia. We also performed a meta-analysis based on all published population-based association studies on the topic including our own. The results of both our case-control study in the Chinese Han population and the meta-analysis yield no significant evidence for association, which suggests that the genetic polymorphisms within RGS4 are unlikely to confer an increased susceptibility to the etiology of schizophrenia.