A family-based study of the IL3RA gene on susceptibility to schizophrenia in a Chinese Han population

Schizophrenia has been observed to be associated with various abnormalities in cytokines and cytokine receptors that have been one of the recent focal points of immunological research in schizophrenia. Recent reports have showed that IL-3 gene, colony stimulating factor 2 receptor alpha (CSF2RA) and IL-3 receptor alpha (IL3RA) are associated with schizophrenia. The aim of this study was to investigate IL3RA gene variants in schizophrenia among a Chinese population by using a family-based association approach. Our sample included 101 Chinese parent-offspring trios of Han descent. All subjects were genotype for IL3RA-rs6603272 and -rs6645249 using PCR techniques. Single marker analysis showed a significant association for rs6603272 (X(2)=5.15, df=1, P=0.023), but not for the rs6645249. However, there was a significant genotypic association of both the polymorphisms with schizophrenia (for rs6603272, X(2)=6.15, df=2, P=0.046; for rs6645249, X(2)=21.79, df=2, P=1.85e-005). Haplotype TDT was statistically significant (X(2)=5.14, df=1, P=0.023), with the rs6603272(T)-rs6645249(G) haplotype significantly associated with schizophrenia (OR=1.66; 95% CI=1.08-2.55). In conclusion, our family-based association study also revealed a small but significant contribution of the IL3RA variants to susceptibility to schizophrenia in a Chinese population.