Association of polymorphisms of heat shock protein 70 with susceptibility to noise-induced hearing loss in the Taiwanese population.

Noise-induced hearing loss (NIHL) is the major cause of adult sensorineural hearing loss. It is a complex disease caused by the interaction of environmental and genetic factors. Previous studies found that heat shock proteins (HSPs) were associated with the development of NIHL. Specifically, polymorphisms in the heat shock protein 70 (HSP70) gene family are associated with a susceptibility to NIHL. In this study, three single nucleotide polymorphisms (SNPs) of the HSP70 family (SNP1: rs2075800; SNP2: rs1043618; SNP3: rs2763979) were genotyped in 349 noise-exposed Taiwanese workers. The subjects were categorized into noise-susceptible (NS; n = 27) and general susceptibility (GS; n = 322) groups by the change of a 4K-weighted audiometric average in an interval of 5 years. The G/C genotype of SNP2 was found to be associated with NIHL susceptibility (adjusted OR = 2.634; 95% CI = 1.096-6.328). No significant association was found for SNP1 and SNP3 with NIHL susceptibility. Analysis of haplotypes composed of these three SNPs revealed a significant association between NIHL susceptibility and haplotype CCC (OR = 2.197; 95% CI = 1.110-4.370). In conclusion, the genetic polymorphisms in the HSP70 genes seem to be associated with the individual's susceptibility to NIHL in the Taiwanese population. These findings could be used as a reference in the understanding and prevention of NIHL.