Mutations in the GJB2 gene (13q12.11, OMIM 121011) encoding transmembrane protein connexin 26 result in the nonsyndromic autosomal recessive deafness 1A (DFNB1A, OMIM 220290), which is one of the most common forms of HL in many populations, at least of Caucasian descent [5]. Here, GJB2 is linked to autosomal recessive nonsyndromic hearing loss 1A.