ABSTRACT
Objective:Mutations in the CX(connexin)26 gene (GJB2), encoding the gap\|junction protein. Connexin 26, have been shown to be the major cause of non\|syndromic recessive deafness. Among these mutations, the CX 26 cDNA (35delG) mutation accounts for the majority of this kind of deafness are European and America, but it does not present in China. Therefore, we intend to investigate the mutation hot spot of connexin 26 in China deafness populations. Mathods:The mutation of 233delC was detected by the technique of PCR\|RFLP and analyzed by directly sequencing protocols in 219 patients with kinds of deafness and 50 individuals with normal hearing. Results: The frequency of the 233delC mutation was 47/219(21.5%) in the Chinese population. No mutation was found in group with normal hearing and dominant nonsyndromic hearing loss. The mutation frequency for 233delC was 4 in 15 patients (26.7%) with genetic prelingual deafness and 10 in 50 patients(20.0%) with drug\|deafness. Conclusion: The 233delC mutaion had a high frequency in Chinese population with hearing loss, especially congenital deafness. Our data indicated that specific combinations of GJB2 mutation exist in different populations.