Connexin 26基因233delC突变与中国人先天性耳聋的研究

High frequency mutation of the 233delC in connexin 26 gene in Chinese deafness populations

目的 :Connexin2 6基因突变是引起常染色体隐性遗传 DFNB1和常染色体显性遗传 DFNA3的遗传基础 ,其中的 35 del G的突变在欧美人 DFNB1耳聋患者中的检出率为 70～ 80 % ,但在中国耳聋人群中未检到该点突变。本文旨在筛选中国人耳聋相关的 Connexin2 6基因的突变热点。方法 :采用 PCR- RFL P筛选 2 19例不同耳聋类型的患者和 5 0例听力正常人的 Connexin 2 6基因 2 33del C的突变 (2 1.5 % )。结果 :2 19例耳聋患者中共发现了 47例 Connexin 2 6基因2 33del C的突变 (2 1.5 % )。在先天性耳聋患者中 2 33del C的突变率为 33% ,遗传性语前聋患者为 2 6 .7%。 5 0例药物性致聋的患者有 10例发生突变。遗传性及散发性进行性感音神经性耳聋和听力正常人未检测到 2 33delc突变。结论 :Connexin2 6基因 2 33del C突变在中国先天性耳聋人群中发生频率较高 ,与欧美人不同。我们的结果表明 ,Connexin2

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.