CDH23 Gene: Function, Mutations, and Associated Diseases | NCBI, OMIM, ClinVar

The CDH23 gene encodes cadherin 23, a member of the cadherin superfamily of calcium-dependent cell adhesion proteins. Cadherin 23 is essential for the formation and maintenance of hair cell stereocilia bundles in the inner ear and for photoreceptor cell function in the retina. Mutations in CDH23 cause Usher syndrome type 1D (USH1D), characterized by congenital profound hearing loss, vestibular dysfunction, and retinitis pigmentosa, as well as non-syndromic autosomal recessive deafness (DFNB12) and autosomal dominant deafness (DFNA12). The protein contains multiple extracellular cadherin repeats, a transmembrane domain, and a cytoplasmic tail that interacts with other Usher syndrome proteins.

Tissue Expression

Cell Line Expression

Hotspot Mutations

Mutation functional classification

• Usher syndrome interactome (cadherin 23

• harmonin

• sans

• etc.)

• Stereocilia bundle assembly and maintenance

• Photoreceptor cell calyceal process formation

Cadherin 23 is a large, single-pass transmembrane protein with 27 extracellular cadherin repeats, a transmembrane domain, and a cytoplasmic region containing a PDZ-binding motif. It forms calcium-dependent homophilic interactions and interacts with other Usher syndrome proteins (e.g., harmonin, sans) to link stereocilia together and to the actin cytoskeleton. In the retina, it localizes to the calyceal processes of photoreceptor cells. The protein is critical for mechanotransduction in hair cells and for photoreceptor survival.