GJB6 and sensorineural hearing loss disorder: Patient 3 is a 48-year-old man with neurosensory deafness caused by a mutation in the compound heterozygosity of GJB6 [del(GJB6-D13S1830) and del(GJB6-D13S1854)] who had been studied in 2009 after having had twins with hearing impairment (cases 7–8) due to a GJB6 mutation in heterozygosity.