However, this large deletion has not been detected in Turkish, Italian, Austrian, Greek Cypriot and Chinese nonsyndromic hearing loss patients [90-94], suggesting that other mutations, both within DFNB1 and elsewhere may be involved in epistatic interactions with GJB2. We recently provided an evidence that mutations in the Cx26 and Cx31 genes can interact to cause hearing loss in digenic heterozygotes. Here, GJB2 is linked to hearing loss disorder.