By Dr. Steve Rose on April 4, 2017
USH2A is a target for retinal-disease researchers, because mutations in the gene are the most common cause of Usher syndrome type 2, which causes combined vision loss from retinitis pigmentosa (RP) and hearing loss from inner ear dysfunction. Also, USH2A mutations are a leading cause of RP without hearing loss (i.e., non-syndromic).
A major challenge in providing prognoses for USH2A patients — and designing clinical trials for potential therapies — is the wide variability in the severity and rate of progression of the disease and its symptoms. Researchers have identified hundreds of USH2A mutations — misspellings in the patients’ genetic code. Some of these defects lead to RP only. Others cause Usher syndrome.