Usher Syndrome, Type IB (MYO7A)
Usher syndrome type 1B is an autosomal recessive, pan-ethnic disease caused by pathogenic variants in the gene MYO7A. The disease is characterized by congenital bilateral sensorineural deafness, which may be treated by cochlear implants; hearing aids do not help. Progressive loss of vision due to retinitis pigmentosa begins in childhood. Retinitis pigmentosa first presents with night blindness, but progresses to tunnel vision and eventually blindness. Patients also have problems with their balance and therefore experience developmental delay. The presence of several specific variants result in a later-onset Usher syndrome, called Usher syndrome III. Life expectancy is not reduced.
For information about carrier frequency and residual risk, please see the residual risk table.