Targeted Next-Generation Sequencing Successfully Detects Causative Genes in Chinese Patients with Hereditary Hearing Loss

Aims: We attempted to identify the genetic epidemiology of hereditary hearing loss among the Chinese Han population using next-generation sequencing (NGS). Materials and Methods: The entire length of the genes GJB2, SLC26A4, and GJB3, as well as exons of 57 additional candidate genes were sequenced from 116 individuals suffering from hearing loss. Results: Thirty potentially causative mutations from these 60 genes were identified as the likely etiologies of hearing loss in 67 of the cases. In our study, SLC26A4 and GJB2 were the most frequently affected genes among the Chinese Han population with hearing loss. Collectively, they account for 52.8% of the cases, followed by MTRNR1, PCDH15, and TECTA. These data also illustrate that NGS can be used to identify rare alleles responsible for hereditary hearing loss: 22 of the 30 (73.3%) genes identified with mutations are rarely mutated in hereditary hearing loss and only account for 21.5% (42/195) of the total mutation frequency, explaining no more than 2% for each gene. These rarely mutated genes would be missed by conventional diagnostic sequencing approaches. Conclusions: NGS can be used effectively to identify both the common and rare genes causing hereditary hearing loss.