Cadherins are calcium-dependent cell adhesion proteins. They preferentially interact with themselves in a homophilic manner in connecting cells. CDH23 is required for establishing and/or maintaining the proper organization of the stereocilia bundle of hair cells in the cochlea and the vestibule during late embryonic/early postnatal development. It is part of the functional network formed by USH1C, USH1G, CDH23 and MYO7A that mediates mechanotransduction in cochlear hair cells. Required for normal hearing. Interacts with USH1C and USH1G (By similarity). antiparallel heterodimer with PCDH15. Isoform C1: Interacts with CAMSAP3; leading to inhibit CAMSAP3 ability to induce microtubule bundle formation (PubMed:27349180). In adult animals relatively high levels of expression are found in testis, skeletal muscle, heart, eye and thymus, and lower expression in kidney, lung and brain. Found in the sensory hair cells of the inner ear. Three calcium ions are usually bound at the interface of each cadherin domain and rigidify the connections, imparting a strong curvature to the full-length ectodomain. Cadherin repeats 1 and 2 mediate calcium-dependent heterophilic interaction with PCDH15. Defects in Cdh23 are the cause of waltzer (v) phenotype. Waltzer mice are characterized by deafness and vestibular dysfunction due to degeneration of the neuroepithelium within the inner ear.