ObjectiveTo investigate the correlation of the polymorphism of locus rs2391191 of D-amino acid oxidase activator (DAOA) gene and the incidence and age of first onset of schizophrenia of Chinese Han patients.MethodsThe polymorphism of locus rs2391191 of DAOA gene of 359 patients with early-onset schizophrenia (early onset group, the age of first onset of schizophrenia ≤18 years old), 443 patients with non early onset schizophrenia (non early onset group, the age of first onset of schizophrenia >18 years old), and 302 normal controls (control group) was detected by TaqMan genotyping technique. The correlation of risk allele with the age of first onset of schizophrenia was investigated by the survival analysis.ResultsCompared with the control group, the distribution of allele and genotype frequencies of locus rs2391191 of the early onset group and non early onset group was statistically different (χ2=7.79, P=0.01; χ2=10.01, P=0.01 and χ2=5.17, P=0.02; χ2=7.80, P=0.02). Kaplan-Meier analysis showed that the age of first onset of schizophrenia of patients of the early onset group who carried the risk allele was statistically different from that of patients who didn't carried the risk allele (χ2=4.55, P=0.03).ConclusionThe polymorphism of locus rs2391191 of DAOA gene was significantly correlated with the incidence and age of first onset of schizophrenia of Chinese Han patients.