吕梁地区遗传性耳聋GJB2基因和mtDNA 1555位点的突变筛查

The mutation screening of the hereditary deafness associated gene GJB2 and site mtDNA 1555 from district of Lvliang

目的通过对吕梁地区96例耳聋患者的GJB2基因和mtDNA 1555位点突变筛查,了解该地区的基因突变情况及热点突变位点。方法采用聚合酶链式反应(PCR)扩增96例标本的GJB2基因和mtDNA 1555位点所在区段,产物酶切、测序分析。结果 96例标本共计检出10个GJB2基因突变位点,与编码连接蛋白的非综合征耳聋突变数据库(http://davinci.crg.es/deafness/index.php?seccion=mut_db&db=nonsynd)比对,8个位点已见报道,其中包括4个多肽位点c.79 G>A、c.341 A>G、c.608 T>C、c.457 G>A和4个致病位点c.235delC、c.109 G>A、c.176-c.191 del16和c.299-c.300delAT,其中,c.235delC是主要突变方式,携带率为6.25%(12/192);2个位点(c.IVS1-35 G>T和c.88A>G)属首次报道。酶切发现1例患者携带mt.1555纯合突变,后经测序发现还携带有mt.1438A>G突变位点。结论吕梁地区耳聋患者以GJB2 c.235delC为主要致病位点,本次研究结果为吕梁地区的耳聋预防奠定了基础,同时为今后临床医师诊断、治疗及遗传咨询提供了参考。

Objectives： Learn the situation and the hot -spot mutations in Ldiang by screening the gene GJB2 and site mtDNA 1555 from 96 deaf patients. Methods： PCR was used for amplifying the piece of gene where gene GJB2 and site mtDNA 1555 are located followed by enzymicutting and sequencing. Results ： 10 mutations sites of GJB2 gene were detected in 96 abnormal samples. Comparing with hereditary deafness, 8 sites has been reported, four polypeptide sites, c. 79 G 〉 A, c. 341 A 〉 G, c. 608 T 〉 C, c. 457 G 〉 A, four pathogenic sites, e. 235delC, c. 109 G 〉 A, e. 176 - e. 191 dell6, c. 299 - c. 300delAT. GJB2 235delc is the main pathogenic mutation site, and the mutation rate are 6. 25% （12/192） . 2 mutation （c. IVSI -35 G 〉T 和 c. 88 A 〉 G） were newly reported, mr. 1555 homozygous mutant was detected from one patient by cutting, mt. 1438A 〉 G homozygous mutant was detected in by sequencing. Conclusion： GJB2 c. 235delC is the main pathogenic site in lvliang, the foundation of deafness preventing has been established for lvliang from this research, in addion, deafness mutations database were enriched where by the references for clinical diagno- sis, treatment and genetic counseling are provided for the future use.