GJB2 and deafness: Among a number of deafness-related genes (the Hereditary Hearing LossHomepage, http://hereditaryhearingloss.org/), mutations in GJB2,SLC26A4, GJB3, and mitochondrial 12SrRNA gene (MT-RNR1) are found to be more frequent.Mutations in GJB2 and SLC26A4 have been reported tocause autosomal recessive nonsyndromic hearing loss, while the inheritance pattern ofGJB3 mutations is not quite clear (Nishio and Usami, 2015).