Polymorphisms in genes encoding aquaporins 4 and 5 and estrogen receptor α in patients with Ménière's disease and sudden sensorineural hearing loss.

AIMS The etiologies of Ménière's disease and idiopathic sudden sensorineural hearing loss (SSNHL) remain unclear. The homeostasis of the water and blood circulation in the inner ear is essential for maintaining its hearing and equilibrium functions, and aquaporins and estrogen are involved in the fluid or ion balance in the inner ear. We investigated the associations between genetic polymorphisms in aquaporin 4 (AQP4, rs2075575), aquaporin 5 (AQP5, rs3736309), and estrogen receptor α (ERα1, rs2234693; ERα2, rs9340799) and susceptibility to Ménière's disease or SSNHL. MAIN METHODS We compared 86 patients affected by Ménière's disease, 85 patients affected by SSNHL, and 2136 adults who were participants in a comprehensive longitudinal study of aging. KEY FINDINGS With the AQP5 polymorphism, the odds ratio for Ménière's disease was 0.676 (95% confidence interval: 0.477-0.957) after adjustment for age and sex, when an additive genetic model was used. The AQP5 polymorphism entailed no significant risk of SSNHL and the polymorphisms of AQP4, ERα1, and ERα2 entailed no significant risk of Ménière's disease or SSNHL in the additive genetic model, regardless of adjustments for age and sex. SIGNIFICANCE Our study suggests that the variant G allele of AQP5 polymorphism rs3736309 reduces the risk of Ménière's disease.