Association Analysis Between The Prodynorphin Gene And The Dopamine D₂ Receptor Gene And Schizophrenia

Objective:To investigate the relationship between the Prodynorphin gene and the dopamine D₂ receptor gene and the susceptibility of schizophrenia in Chinese Han population and explore the effect of interaction of the two genes on the presence of schizophrenia.Method:Genotypes and alleles of 128 patients and 124 healthy persons were examined with polymerase chain reaction(PCR) and restriction fragment length polymorphism(RFLP) technique.Result:No significant differences in alleles and genotypes frequencies in PDYN gene were observed between schizophrenic patients and controls(x²=0.44,P=0.931;x²=1.35,P=0.930);The frequency of DRD₂- 141C Del allele were significantly decreased in the schizophrenic subjects compared with the controls(x²=10.60,P=0.001);The frequency of the allele 3 of PDYN was more higher in schizophrenic patients than in controls who carried DRD₂- 141C Del allele(x²=6.19,P=0.013).Conclusion:The decrease of DRD₂-I41C Del allele may affect the susceptibility of schizophrenia;PDYN gene polymorphism alone does not alter the risk for schizophrenia but,by an epistatic interaction with the Del allele of the DRD₂ gene,may contribute to the susceptibility to this disorder.