Branchio-oto-renal syndrome: comprehensive review based on nationwide surveillance in Japan.

Branchio-oto-renal (BOR) syndrome is an autosomal dominant disorder characterized by branchiogenic malformation, hearing loss and renal anomalies. The prevalence of BOR syndrome is 1/40,000 in Western countries, and nationwide surveillance in 2009-2010 identified approximately 250 BOR patients in Japan. Three causative genes for BOR syndrome have been reported thus far: EYA1, SIX1, and SIX5, but the causative genes for approximately half of all BOR patients remain unknown. This review article discusses the epidemiology, clinical symptoms, genetic background and management of BOR syndrome.