The mouse Ames waltzer hearing-loss mutant is caused by mutation of Pcdh15, a novel protocadherin gene

The neuroepithelia of the inner ear contain hair cells that function as mec hanoreceptors to transduce sound and motion signals. Mutations affecting th ese neuroepithelia cause deafness and vestibular dysfunction in humans(1-3) . Ames waltzer (av) is a recessive mutation found in mice that causes deafn ess and a balance disorder associated with the degeneration of inner ear ne uroepithelial. Here we report that the gene that harbours the av mutation e ncodes a novel protocadherin. Cochlear hair cells in the av mutants show ab normal stereocilia by 10 days after birth (P10). This is the first evidence for the requirement of a protocadherin for normal function of the mammalia n inner ear.