Usher syndrome (USH) is a group of autosomal recessively inherited disorders characterized by deafness and vision loss. Three clinical types USH1, USH2, and USH3, are distinguished on the basis of severity of hearing loss and the presence or absence of vestibular dysfunction. USH1 patients are congenitally profoundly deaf, and have vestibular dysfunction as well as prepubertal onset of progressive retinitis pigmentosa (RP). USH2 is characterized by congenital mild hearing impairment with normal vestibular responses. USH3 is characterized by a progressive hearing loss, a variable vestibular dysfunction, and RP. USH shows significant genetic heterogeneity, and at least 11 distinct loci have been identified and genes for 9 of them have been cloned. Recently, USH4 caused by mutations in ARSG has been reported.
Nervous system disease
Human diseases in ICD-11 classification [BR:br08403]
20 Developmental anomalies
Multiple developmental anomalies or syndromes
LD2H Syndromic genetic deafness
H00779 Usher syndrome