Single nucleotide polymorphisms of hOGG1, APEX1 and XRCC1 genes and their association with noise-induced hearing loss among noise-exposed workers

Objective The aim of this study was to determine single nucleotide polymorphisms (SNPs)of hOGG1, APEX1 and XRCC1 genes and to identify their association with noise-induced hearing loss(NIHL) in noise-exposed workers.

Methods A cross-sectional study was performed in the noise-exposed workers in a chemical fiber factory located in Jiangsu Province, including 585 NIHL cases and 619 reference workers according to the measurement of noise level in their workplaces and examination of pure tone audiometry. The SNPs of selected genes were genotyped by TaqMan-PCR technique.

Results Three candidate genes (hOGG1, XRCC1 and APEX1) were screened. The results of logistic regression analysis showed that under the dominant model, rs2072668 CC+CG genotype may be a risk factor for NIHL compared with rs2072668 GG genotype and its adjusted OR value(95%CI) was 1.40(1.10-1.78)and 2.11(1.16-3.82) while the annual cumulative noise exposure(CNE) was 90-95 dB (A). While the annual CNE was under 90 dB (A), rs 1130409 GG+GT genotype may be a risk factor for NIHL compared with TT genotype and its adjusted OR value (95%CI) was 2.76 (1.13-6.73). Haplotype analysis showed that CTG (rs2072668-rs1799782-rs2230409)may be a risk factor for NIHL and its adjusted OR value (95%CI) was 1.78(1.21-2.61).

Conclusion Rs2072668 CC+CG genotype may increase the risk of NIHL in noise-exposed workers, which suggested that the SNPs of hOGG1 may be associated with the susceptibility of NIHL.