OBJECTIVETo investigate the genetic association between schizophrenia and polymorphism of D-amino acid-oxidase (DAAO) gene.

METHODSA total of 112 parent/offspring trios in which the proband met the Amerecan Classification and Diagnostic Criteria for Mental Disorders (Fourth Revised Edition) were included in this study. Correlation analysis between schizophrenia and DAAO gene polymorphism and haplotype relative risk analysis were conducetd by using PCR and SNP typing in all the nuclear families.

RESULTSThe rs3918347 allele was correlated to schizophrenia (P = 0.014). Allele A was a protective factor (Z = -2.37) and allele G the hazard factor (Z = 2.37). The frequency of rs3918347 allele A was 0.41 and that of the allele G was 0.59. The rs3741775, rs3825251 and rs4964770 alleles were not associated with schizophrenia. Three haplotypes of C/G in the rs3825251-rs3918347, G/T in the rs3918347-rs4964770, C/G/T in the rs3825251-rs3918347-rs4964770 were associated with schizophrenia (P = 0.021, 0.036, and 0.028, with genotype frequencies of 0.33, 0.28, and 0.15, respectively).

CONCLUSIONThe nucleotide polymorphism of DAAO gene is associated with schizophrenia in Chinese population.