Clinical Genetic Testing for Hearing Loss: Implications for Genetic Counseling and Gene-Based Therapies

Abstract

Genetic factors contribute significantly to congenital hearing loss, with non-syndromic cases being more prevalent and genetically heterogeneous. Currently, 150 genes have been associated with non-syndromic hearing loss, and their identification has improved our understanding of auditory physiology and potential therapeutic targets. Hearing loss gene panels offer comprehensive genetic testing for hereditary hearing loss, and advancements in sequencing technology have made genetic testing more accessible and affordable. Currently, genetic panel tests available at a relatively lower cost are offered to patients who face financial barriers. In this study, clinical and audiometric data were collected from six pediatric patients who underwent genetic panel testing. Known pathogenic variants in MYO15A, GJB2, and USH2A were most likely to be causal of hearing loss. Novel pathogenic variants in the MYO7A and TECTA genes were also identified. Variable hearing phenotypes and inheritance patterns were observed amongst individuals with different pathogenic variants. The identification of these variants contributes to the continually expanding knowledge base on genetic hearing loss and lays the groundwork for personalized treatment options in the future.

Keywords: congenital; genetic panel testing; hearing loss; hereditary; novel variant; sensorineural.

Figure 1

Serial pure tone average thresholds of six patients with genetic panel testing. The serial audiograms represent the average dB between the left and right ears. Audiograms for (a) patient 1—because this patient received care and follow-up at another facility, further audiologic information could not be obtained; (b) patient 2; (c) patient 3; (d) patient 4; (e) patient 5; (f) patient 6. For patients 2 and 6, broken lines indicate aided thresholds.