Screening of GJB2 mutations in Chinese population

The GJB2 gene (connexin 26) has been shown to be responsible for DFNB1 and DFNA3. We screened the GJB2 gene in 488 patients with prelingual deafness(Group 1), 124 with postlingual deafness(Group 2), and 117 normal hearing subjects (Group 3). We found that, in Group 1, 65 patients (13.32%) were homozygotes or compound heterozygotes and 51 patients (10.45%) carried a single pathogenic mutation. The 235delC mutation was the most frequent mutation, accounting for 73.22% of the known pathogenic alleles in Group 1. No homozygotes or compound heterozygotes were detected in Group 2 or Group 3. Some postlingual deaf patients (2.42%) and normal hearing subjects(4.27%) were 235delC carriers. Our preliminary data indicate that 235delC, the most frequent mutation identified in this study, is a major cause for prelingual deafness.