CHD7 gene mutations are the main cause of CHARGE syndrome,[13] and the CDH23 gene, which encodes otocadherin, plays an important role in the structure and function of hair cell stereocilia.[14] Mutations in the CDH23 gene can lead to non-syndromic hearing loss (NSHL) with only auditory manifestations or to Usher syndrome type 1D (USH1D) characterized by hearing loss, retinal pigment deposits, and vestibular dysfunction. This evidence concerns the gene CDH23 and nonsyndromic deafness.