These signals are then detected by the auditory nerve fibers, transmitted to the brain and interpreted as sound. In the cochlea, stereocilia are located on the apical surface of inner ear hair cells (HC) and are responsible for transducing mechanical stimuli from sound pressure waves into chemical signals. The proteins encoded by these genes form complexes that play critical roles in the development and maintenance of cellular structures within the inner ear and retina, which have minimal capacity for repair or regeneration. There are currently nine confirmed and two suspected USH-causative genes, and a further three candidate loci have been mapped.

Three clinically distinct types of USH have been identified, decreasing in severity from Type 1 to 3, with symptoms of sensorineural hearing loss (SNHL), retinitis pigmentosa (RP), and vestibular dysfunction. Usher syndrome (USH) is an autosomal recessive (AR) disorder that permanently and severely affects the senses of hearing, vision, and balance. 6School of Pharmacy and Biomedical Sciences, Faculty of Health Sciences, Curtin University, Bentley, WA, Australia.5Centre for Cell Therapy and Regenerative Medicine, The University of Western Australia, Perth, WA, Australia.4Ear Sciences Centre, The University of Western Australia, Nedlands, WA, Australia.3School of Human Sciences, The University of Western Australia, Nedlands, WA, Australia.2Emergency Medicine, The University of Western Australia, Nedlands, WA, Australia.1Ear Science Institute Australia, Nedlands, WA, Australia.

Usher syndrome chromosome affected