Thus, the proportion of pathogenic biallelic variants of the GJB2 gene (13q11-q12) [4] encoding the intercellular gap junction protein connexin 26 (Cx26) [5, 6] leading to autosomal recessive deafness type 1A (DFNB1A, OMIM #220290) [7] is significant, and in some populations, it is up to 50–60% [8–10]. This evidence concerns the gene GJB2 and autosomal recessive nonsyndromic hearing loss 1A.