No genetic association between polymorphisms in the AMPA receptor subunit GluR4 gene ( GRIA4) and schizophrenia in the Chinese population

The glutamatergic dysfunction hypothesis of schizophrenia suggests genes involved in glutamatergic transmission as candidates for schizophrenia-susceptibility genes. It has recently been reported that some haplotypes in the AMPA receptor subunit GluR4 Gene ( GRIA4), which is located on chromosome 11q22, are positively associated with schizophrenia in the Japanese population. In order to assess the role of GRIA4 in schizophrenia, we examined three reported positive SNPs (single nucleotide polymorphisms): rs609239, rs641574 and rs659840 at the GRIA4 locus in schizophrenic cases ( n = 372) and controls ( n = 392) of the Chinese population. Although we had observed similar allele and genotype frequencies compared with that in the Japanese population, no evidence was found for association with the disease in the analysis of either single nucleotide polymorphisms (all P-values > 0.300) or haplotype relative risk (all P-values > 0.088). Our results suggest that the three SNPs of GRIA4 are unlikely to play a major role in the susceptibility to schizophrenia in the Chinese population.