GJB2 and hearing loss, autosomal recessive: In several populations, the most frequent cause of non-syndromic autosomal recessive deafness occurs because of an altered connexin 26 protein, a communicating gap junction protein encoded by the gene GJB2 (13q11-12) (OMIM 121011).6, 7, 8, 9, 10, 11, 12, 13