Racial and Ethnic Disparities in Genetic Testing for Hearing Loss: a Systematic Review and Synthesis

Abstract

Racial/ethnic disparities in the diagnostic efficacy of genetic testing for hearing loss has been described. These disparities may relate to differences in variant classification between different racial/ethnic groups, which may in turn derive from disparate representation of these groups in the published literature. We sought to quantify racial/ethnic disparities in the published literature on the human genetics of hearing loss. We conducted a search of PubMed for articles describing single-gene, multiple-gene, or whole-exome sequencing for individuals with sensorineural hearing loss. Data on the populations studied, including race/ethnicity and/or region of origin, subjects tested, and method of testing, were extracted. 1,355 unique populations representing 311,092 subjects from 1,165 studies were included. Overall, White and Asian populations and subjects were equivalently represented, but Latinx, Black, and Native American/Hawaiian groups were significantly underrepresented; over 96% of all subjects in the published literature were White or Asian. Within racial/ethnic groups, the majority of subjects derived from a small subset of countries. The observed racial/ethnic disparity was greater for multiple-gene and whole-exome sequencing than for single-gene sequencing. These findings illustrate the large disparity in published literature on the genetics of hearing loss, and demonstrate the need for increased representation of Latinx, Black, and Native American populations.