RESUMO
<p><b>OBJECTIVE</b>To investigate the relevance between single nucleotide polymorphisms (SNPs) in CHRNA3-CHRNB4-CHRNA5 gene cluster and DNA damage levels in the coke oven workers.</p><p><b>METHODS</b>A total of 309 male subjects from a steel plant in Northern China were divided into high exposure group (154 workers) and low exposure group (155 workers) according to the concentrations of plasma benzoapyrene-r-7, t-8, t-9, c-10-tetrahydrotetrol-albumin (BPDE-Alb) adducts. DNA damage levels of peripheral blood lymphocytes were examined by comet assay. Allelic discrimination of SNPs in CHRNA3-CHRNB4-CHRNA5 gene cluster were detected using Matrix-assisted laser desorption/ionization mass spectrometry.</p><p><b>RESULTS</b>The Olive tail moment (OTM) (1.23 ± 1.05) of peripheral blood lymphocytes in the high exposure group was significantly higher than that (0.80 ± 1.07) in the low exposure group (P < 0.01). In the high exposure group, OTM (1.64 ± 0.17) of subjects with rs667282CC genotype was significantly higher than those (0.95 ± 0.13 or 1.09 ± 0.11) of subjects with rs667282CT genotype or rs667282TT + CT genotype (P < 0.01); OTM (1.60 ± 0.17) of subjects with GG genotype at rs12910984 site was significantly higher than those (0.92 ± 0.13 or 1.07 ± 0.10) of subjects with AG genotype or AG + AA genotype (P < 0.01); OTM (1.35 ± 0.17 or 1.64 ± 0.17) of the TA/TA or CG/CG diplotype carriers was significantly higher than that (0.89 ± 0.13) of TA/CG diplotype carriers (P < 0.05). However, the relevance between genotypes of these SNPs and the DNA damage levels was not found in the low exposure group.</p><p><b>CONCLUSION</b>The rs667282CC genotype and rs12910984GG genotype on CHRNA3-CHRNB4-CHRNA5 gene cluster are associated with increased DNA damage levels in the high PAHs exposure group.</p>