Association of polymorphisms in heat shock protein 70 genes with the susceptibility to noise-induced hearing loss: A meta-analysis

BACKGROUND Several case-control studies reported the relationship between single nucleotide polymorphisms (SNPs) in HSP70 genes and noise-induced hearing loss (NIHL). However, their conclusions are conflicting. This meta-analysis aims to identify the association of HSP70 variants and NIHL susceptibility. METHOD A systematical literature search was performed in PubMed, Web of Science, EMBASE, and Wanfang Chinese database. The pooled odds radio (OR), 95% confidence interval (CI) and p value were calculated in fixed- or random-effects model according to the I2 value in the heterogeneity test. RESULTS Four articles containing five studies, including 633 cases and 926 controls, were included. Under the allele, homozygote and dominant model, the pooled ORs (95%CI, p-value) of rs1061581 were 1.32 (1.06-1.67, p = 0.019), 1.93 (1.10-3.36, p = 0.021) and 1.455 (1.408-2.019, p = 0.025), respectively. In addition, a significant association was found between rs2227956 in Caucasians and the NIHL susceptibility under all five genetic models. We did not discover evidence sufficient to prove the associations between the other three SNPs (rs1043618, rs2763979 and rs2075800) and the NIHL susceptibility. CONCLUSION This meta-analysis indicated that the two HSP70 variants, rs1061581 and rs2227956, may serve as genetic susceptibility factors for NIHL. Larger scale studies are required to further update the results.