Necessary for elongation and maintenance of inner and outer hair cell stereocilia in the organ of Corti in the inner ear. Defects in WHRN are the cause of deafness autosomal recessive type 31 (DFNB31). DFNB31 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. Defects in WHRN are the cause of Usher syndrome type 2D (USH2D). USH is a genetically heterogeneous condition characterized by the association of retinitis pigmentosa and sensorineural deafness. Age at onset and differences in auditory and vestibular function distinguish Usher syndrome type 1 (USH1), Usher syndrome type 2 (USH2) and Usher syndrome type 3 (USH3). USH2 is characterized by congenital mild hearing impairment with normal vestibular responses. 4 isoforms of the human protein are produced by alternative splicing. Note: This description may include information from UniProtKB.