Association of metabolic and DNA repair enzyme gene polymorphisms and DNA damage in coke-oven workers

Abstract

To investigate the association of polymorphisms of metabolic and DNA repair enzyme genes and DNA damage in peripheral blood lymphocytes in coke-oven workers. One hundred and forty-four coke-oven workers and 50 controls were recruited in this study. Urinary 1-hydroxypyrene (1-OHP) levels were measured as the internal dose of polycyclic aromatic hydrocarbons exposure. DNA damage was detected by alkaline comet assay, and the value of 1.74 was used as the cut-off value to determine whether the individual's DNA damage was positive. The genotypes of CYP1A1, CYP2E1, GSTP1, NQO1, mEH and XRCC1 were determined by PCR-based methods. With adjustment for urinary 1-OHP, age, sex, multiple analysis of covariance was used to study the association between genotypes and the ln-transformed olive TM and multiple logistic regression was used to calculate the adjusted OR and the 95% CI for the risk of DNA damage. In 144 coke-oven workers, with adjustment for urinary 1-OHP, coking history and sex, the olive TM was significantly higher with XRCC1 280His allele than those with Arg allele (5.6 vs. 2.8, P < 0.01). The subjects with XRCC1 280His allele also have significantly higher risk for DNA damage than subjects with Arg allele (adjusted OR = 2.66, 95% CI = 1.00-7.14, P = 0.05) and the subjects with GSTP1 104Val allele have higher risk for DNA damage than subjects with Ile allele (adjusted OR = 1.90, 95% CI = 0.94-3.85, P = 0.07). XRCC1 and GSTP1 polymorphisms might influence the susceptibility of DNA damage in occupational PAH-exposed coke-oven workers.