Association Between Genetic Variations in POU4F3 and Susceptibility of Noise-Induced High Frequency Hearing Loss

Objective To investigate whether POU4F3 single nucleotide polymorphisms (SNPs) are associated with susceptibility to the development of noise-induced high frequency hearing loss in a Chinese population.

Methods A 1:1 matched case-control study was performed, including 248 cases whose average hearing threshold was more than or equal to 40 dB in high frequency and 248 controls whose average hearing threshold was less than 25 dB in high frequency and vocal speech frequency. Information of the subjects was gathered by questionnaire, physical tests, and pure-tone audiometry. Rs1368402 and rs891969 were genotyped using SNPscan^TM multiplex SNP genotyping kit. Continuous variables and categorical variables were analyzed by t-test and chi-square test respectively. Conditional logistic regression models were used to assess the associations between the genotypes and noise-induced high frequency hearing loss.

Results After adjusting for smoking, drinking, hypertension, and cumulative noise exposure (CNE), there were no significant differences in the distribution of genotypes and alleles frequencies of POU4F3 rs1368402 and rs891969 between the case and control groups (P>0.05). After stratified by CNE, when CNE>95 dB(A), compared with rs1368402 CC/CA genotypes, those carrying AA genotype had a significantly increased risk of noise-induced high frequency hearing loss (adjusted OR=1.547, 95%CI=1.002-2.389, P < 0.05); compared with rs891969 AA/GA genotypes, those carrying GG genotype had a significantly increased risk of noise-induced high frequency hearing loss (adjusted OR=1.650, 95%CI=1.032-2.639, P < 0.05). After stratified by noise exposure levels, smoking, drinking, and hypertension, there were no significant differences between the two groups (P>0.05). According to haplotype analysis, no statistical difference was found between the case and control subjects (P>0.05).

Conclusion The results suggest that POU4F3 genetic variants may not modify the susceptibility to noiseinduced high frequency hearing loss. But interactions are found between SNPs and noise, which may affect the susceptibility to noise-induced high frequency hearing loss. However, the differences are not significant after Bonferroni correction.