OBJECTIVETo investigate the association between ERCC6 gene polymorphisms and peripheral blood lymphocyte DNA damage among the workers in coking plant.

METHODSBy cluster sampling, 379 coke oven workers having worked for 8 hours were included in the exposure group, 398 coke oven workers having rested for more than 16 hours were included in the recovery group, and 398 workers having never been exposed to polycyclic aromatic hydrocarbons (PAHs) in the same plant were included in the control group. Lymphocytes were separated from their peripheral venous blood, and single cell gel electrophoresis was used to evaluate DNA damage; TaqMan-MGB probes were used to analyze ERCC6 gene polymorphisms. PHASE 2.0.2 genetic analysis software was used to calculate the haplotypes.

RESULTSThe Olive tail moment (OTM) of lymphocytes in the exposure group was significantly higher than those in the recovery group and control group (-0.86±0.70 vs -1.14±0.68 and -1.13±0.65, P < 0.05). In the exposure group, for workers ≥37 years old, the OTM of lymphocytes in workers carrying CG+GG genotype at rs3793784 locus of ERCC6 gene was significantly lower than that in workers carrying CC genotype (P < 0.05); the OTM of lymphocytes in workers <37years old carrying CC genotype at rs3793784 locus of ERCC6 gene was significantly lower than that in workers ≥37 years old carrying CC genotype (P < 0.05); the OTMof lymphocytes in workers <37 years old carrying CG+GG genotype at rs3793784 locus of ERCC6 gene was significantly higher than that in workers ≥37 years old carrying CG+GG genotype (P < 0.05). For patients with internal exposure, in the 1-hydroxypyrene >4.36 ümol/L group, the OTM of lymphocytes in workers carrying AG+GG genotype was significantly higher than that in workers carrying AA genotype (P < 0.05).

CONCLUSIONDifferent genotypes of ERCC6 gene rs3793784 in peripheral blood lymphocytes of coke oven workers exposed to PAHs have different functions at different ages, suggesting that genotype may interact with age in population exposed to PAHs.