应用聚合酶链反应-限制性片段长度多态技术快速检测中国耳聋人群基因突变热点

目的 通过筛查耳聋基因热点突变:GJB2基因的235delC、SLC26A4基因的IVS7-2A>G和线粒体12S rRNA(12S)基因1555 A>G达到快速诊断耳聋患者.方法 多重PCR扩增包括GJB2、SLC26A4及12S基因的3个片段,限制性片段长度多态分析是否存在相应位点的突变.结果 200例耳聋患者中,共检测出235delC纯合突变18例,杂合突变18例;IVS7-2A>G纯合突变2例,杂合突变13例;1555 A>G突变8例.检测结果均与测序结果相符合.3个热点突变基因的致病单体的检出率为21.7%,基因诊断率为14%.结论 应用聚合酶链反应-限制性片段长度多态技术检测耳聋患者的热点突变是一种快速、简便、高效、经济的耳聋致病基因筛查的方法.

Rapid detection of the hot spot gene mutations in Chinese patients with nonsyndromic hearing loss by polymerase chain reaction-restrictive fragment length polymorphism

Objective To develop a rapid genetic diagnosis technique for the patients with hereditary hearing loss by screening hot spots of mutations, namely 235delC of the GJB2 gene, IVS7-2A>G of the SLC26A4 gene, and 1555A>G of mitochondrial 12S rRNA. Methods Multiple PCR amplification of the three fragments covering the expected mutations in GJB2, SLC26A4 and 12S were carried out and the amplified products were analyzed by restriction fragment length polymorphism (RFLP). Results Eighteen homozygous and 18 heterozygous 235delC, 2 homozygous and 13 heterozygous IVST-2A>G, and 8 homogeneous 1555A>G were detected in the 200 patients with hearing loss. All the results were confirmed by sequencing. The detection rate of the three mutant alleles was 21.7% (71/400+8/200=0. 217) and the genetic diagnosis rate was 14%(18+2+8)/200=0.14]. Conclusion It is a convenient, efficient and economical method to screen the hot spots of mutation in the patient with hereditary hearing loss by using PCR-RFLP.