title: Association of hsp70 polymorphisms with risk of noise-induced hearing loss in Chinese automobile workers.
abstract: Severe noise exposure can induce heat shock proteins (Hsps), and exposure to moderate noise has been reported to confer protection against noise-induced damage to hearing. Whether there is any association of genetic variation in both constitutive and inducible hsp70 genes with noise-induced hearing loss (NIHL) is presently unknown. Using polymerase chain reaction-restriction fragment length polymorphism, we genotyped 3 polymorphisms (+190A/ B, +1267A/B, and +2437A/B) in the hsp70-1 (rs1043618), hsp70-2 (rs1061581), and hsp70-hom (rs2227956) genes, respectively, and investigated the associations of these polymorphisms with risk of developing NIHL in 194 automobile workers working in a similar noise environment as evaluated by audiological assessment. Multivariate logistic regression models were used to assess the associations with the risk genotypes, and Whap software was used to analyze their haplotypes. Our results showed that there was no statistically significant difference in the genotype and allele distributions of hsp70-1, hsp70-2, and hsp70-hom between the NIHL group and the normal group (P > 0.05) with and without adjustment for age, sex, smoking, history of explosive noise exposure, and cumulative noise exposure. However, haplotype analysis revealed that the Hap5 (ie, haplotype +190A/+1267B/+2437A) and Hap6 (ie, haplotype +190A/+1267B/+2437B) were significantly more frequent in the NIHL group than in the normal group (20/9, P = 0.022, and 7/0, P = 0.005, respectively). Compared with Hap1 (ie, +190A/+1267A/+2437A), Hap5 was associated with a nearly 3-fold increased risk of NIHL (adjusted odds ratio, 2.67; 95% confidence interval, 1.13-6.27). Seven of the NIHL patients had Hap6, but none of the controls had this haplotype. Our results suggest that some haplotypes of the hsp70 genes may be associated with a higher susceptibility to NIHL.
authors.affiliation: Institute of Occupational Medicine, The Ministry of Education, Key Laboratory of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, China.
authors.forename: Miao
authors.initials: M
authors.lastname: Yang
authors.forename: Hao
authors.initials: H
authors.lastname: Tan
authors.forename: Qiaoling
authors.initials: Q
authors.lastname: Yang
authors.forename: Feng
authors.initials: F
authors.lastname: Wang
authors.forename: Huiling
authors.initials: H
authors.lastname: Yao
authors.forename: Qingyi
authors.initials: Q
authors.lastname: Wei
authors.forename: Robert M
authors.initials: RM
authors.lastname: Tanguay
authors.forename: Tangchun
authors.initials: T
authors.lastname: Wu
mesh_terms: D000328:Adult; D000483:Alleles; D001301:Audiometry, Pure-Tone; D002681:China / Q000453:epidemiology; D005260:Female; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics*; D006239:Haplotypes; D006304:Health Status; D006317:Hearing Loss, Noise-Induced / Q000453:epidemiology* / Q000209:etiology; D006801:Humans; D008297:Male; D009623:Noise, Occupational / Q000009:adverse effects* / Q000706:statistics & numerical data; D016273:Occupational Exposure / Q000009:adverse effects* / Q000706:statistics & numerical data; D011110:Polymorphism, Genetic; D012307:Risk Factors
chemical_list: D018840:HSP70 Heat-Shock Proteins