As the result of sequencing the GJB2 coding (exon 2) and non-coding (exon 1) regions with flanking sequences, a genetic diagnosis “Nonsyndromic autosomal recessive deafness 1A (DFNB1A)” due to the presence of biallelic GJB2 pathogenic variants was established for 22.3% (49 out of 220) patients. The gene discussed is GJB2; the disease is autosomal recessive nonsyndromic hearing loss 1A.