2022 NHCA Annual Virtual Conference

Noise-induced hearing loss (NIHL) and tinnitus are clinically heterogeneous traits. Noise exposure is a known risk factor. However, substantial phenotypic heterogeneity in these traits remains unexplained after accounting for the effect of noise exposure. This presentation will (1) review the current literature on the genetic basis of NIHL and tinnitus, and (2) will present our case-control genetic association studies on NIHL and tinnitus. Our literature review suggested that genetic variants in several cochlear genes, metabolic enzymes, and structural proteins are associated with NIHL and tinnitus. We found that most genetic studies were conducted on older factory workers exposed to loud traumatic noise and organic solvent. To control for the effect of age-related confounders, we investigated the genetic basis of NIHL and tinnitus in young, healthy musician students. Our sample included 640 music majors aged 18-25 years. We found that a genetic variant in KCNE1 (rs2070358) and CAT (rs12273124) showed a significant association with NIHL. A genetic variant in KCNQ (rs163171) revealed a significant association with tinnitus. Future research is required to build clinically useful polygenic risk models for identifying susceptible individuals well before acquiring permanent NIHL and tinnitus.