Cadherin-23 (CDH23) is an adhesion protein that contains several calcium dependent extracellular (EC) domains. It is required for establishing and/or maintaining the proper organisation of the stereocilia bundle of hair cells in the cochlea and the vestibule during late embryonic/early postnatal development []. CDH23 is part of the tip-links, oblique filaments that interconnect the stereocilia of the hair bundle []. CDH23 is associated with Usher syndrome type 1 (USH1D), isolated deafness (DFNB12) in humans, and deafness and circling behavior in waltzer mice [, ].