CDH23 and hearing loss disorder: Based on the frequencies of 3.7% (including heterozygous cases) of the hearing loss population and 5.7% (including heterozygous cases) of the recessive inherited cases in this study, we confirmed that mutations of CDH23 are an important cause for non-syndromic hearing loss and should be borne in mind next to GJB2 or SLC26A4 screening.