Micronucleus occurrence related to base excision repair gene polymorphisms in Chinese workers occupationally exposed to vinyl chloride monomer.

Abstract

To evaluate whether base excision repair gene polymorphisms contributed to susceptibility of chromosomal damage induced by vinyl chloride monomer (VCM). Cytokinesis block micronucleus test was performed on 185 VCM-exposed workers to detect chromosomal damage in peripheral lymphocytes. The PCR-restriction fragment length polymorphism technique was applied to detect polymorphisms of TDG, PARP1, and APE1 genes. Univariate and multivariate Poisson regression analysis was performed. There was a 1.198-fold increased micronucleus frequency for individuals carrying TDG 199Gly/Ser + Ser/Ser genotypes compared with those carrying Gly/Gly genotype (P < 0.05). Individuals with the combined genotypes of TDG 199Gly/Ser + Ser/Ser and APE1 64Ile/Val + Val/Val had a significantly increased micronucleus frequency compared with those carrying wild-type genotypes for both genes. VCM-exposed workers carrying TDG 199Gly/Ser + Ser/Ser genotypes were susceptible to chromosomal damage. A combination of TDG Gly199Ser and APE1 Ile64Val polymorphisms may modify the risk of chromosomal damage.