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 (ϩ190A/ B, ϩ1267A/B, and ϩ2437A/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 Ͼ 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 ϩ190A/ϩ1267B/ϩ2437A) and Hap6 (ie, haplotype ϩ190A/ϩ1267B/ϩ2437B) were significantly more frequent in the NIHL group than in the normal group (20/9, P ϭ 0.022, and 7/0, P ϭ 0.005, respectively). Compared with Hap1 (ie, ϩ190A/ϩ1267A/ϩ2437A), 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.

Variations in HSP70 genes associated with noise-induced hearing loss in two independent populations

“…Significant results of the single SNP and haplotype analyses were obtained in both sample sets. These results replicate previous findings reported in a study on Chinese noise-exposed workers 32 and indicate that HSP70 genes may be valid NIHL susceptibility genes.…”

“…31 Finally, a significant association was found between NIHL and two haplotypes composed of three polymorphisms located in the three HSP70 genes (rs1043618, rs1061581 and rs2227956) in a Chinese population of automobile workers. 32 In this study, we investigated whether we could replicate the associations that were observed between haplotypes of the HSP70 genes and NIHL 32 in a Swedish and Polish sample set.…”

“…This protection is highly variable between individuals. An association of HSP70 genes with NIHL has been described by Yang et al (2006) in a Chinese sample set of noise-exposed workers. In this study, three polymorphisms (rs1043618, rs1061581 and rs2227956) in HSP70-1, HSP70-2 and HSP70-hom, respectively, were genotyped in 206 Swedish and 238 Polish DNA samples of noise-exposed subjects and analyzed.…”

Heat-shock protein 70-2 BB genotype is associated with reduced risks of the steroid-dependent and refractory phenotypes of ulcerative colitis

“…The HSP70-2 polymorphism was investigated in a selected region of central Japan. Previous studies have indicated that the HSP70-2 gene polymorphism shows variations within the same ethnicities (29,30) and the HSP70-2 genotype distribution in HC subjects also demonstrates a considerable variation compared to a previous study in another area of Japan (11). However, further studies are required in a larger and more diverse population to confirm the influence of this gene on the pathogenesis of UC.…”

Association of Heat Shock Protein 60 With Noise-Induced Hearing Impairment and Electrocardiographic Abnormalities Among Workers Occupationally-Exposed to Noise

“…HSPs can be induced by severe noise exposure (Yang et al, 2006). In the current study (Table 3), a statistically significant difference was found when comparing HSP60 levels among the exposed workers with normal hearing and those with NIHL at low frequencies, but a statistically nonsignificant difference was found at high frequencies.…”