Usher Syndrome

Combined deafness and progressive vision loss from retinitis pigmentosa

Overview

Usher syndrome is an inherited condition that combines sensorineural hearing loss with retinitis pigmentosa, a progressive degeneration of the retina that causes night blindness and gradual narrowing of the visual field. It is the most common genetic cause of combined deafness and blindness. Three main clinical types are recognized: type 1 involves profound congenital deafness and absent vestibular function, type 2 involves moderate to severe congenital hearing loss with normal balance, and type 3 involves progressive hearing and vision loss. It is inherited in an autosomal recessive pattern, and genes involved include MYO7A, USH2A, and CLRN1, whose proteins help organize the stereocilia of hair cells and the photoreceptors of the retina. Genetic testing clarifies the type and prognosis. Cochlear implants are widely used in type 1, and support for families often includes planning for later vision changes. Gene based and other therapies for the retinal component are under investigation.