Otoancorin, also known as OTOA, CT108 or DFNB22, is a 1,153 amino acid protein belonging to the stereocilin family. Expressed in the inner ear and restricted to the interface between the apical surface of sensory epithelia, otoancorin is suggested to act as an adhesion molecule. Otoancorin ensures the attachment of the inner ear acellular gels to the apical surface of the underlying nonsensory cells. Mutations in the gene encoding otoancorin leads to deafness autosomal recessive type 22 (DFNB22), which is a form of sensorineural hearing loss. Sensorineural deafness results from damage to the neural receptors of the inner ear, the nerve pathways to the brain or the area of the brain that receives sound information. Existing as three alternatively spliced isoforms, otoancorin is encoded by a gene located on human chromosome 16p12.2.