非综合征型耳聋患者mtDNA A1555G异质性突变比例与临床表型的关系

Correlation between the percentage of mitochondrial DNA copies with the A1555G mutation and the phenotype of mitochondrial deafness

目的定量检测非综合征型耳聋患者线粒体DNA(mitochondrial DNA,mtDNA)1555突变型/野生型的拷贝数,探讨突变型/野生型比例与临床表型之间的关系。方法建立实时定量PCR技术和扩增阻滞突变系统(Real-time quantitative PCR和Amplification refractory mutation system,RT-ARMS-qPCR系统)对含突变型和野生型mtDNA 1555位点的拷贝数进行定量检测并计算比例。共检测散发组12例、家系组7例异质性突变患者,结合耳聋患者的临床资料,分析突变型与野生型的比例与耳聋严重程度的关系。结果散发组mtDNA A1555G异质性突变的患者中,突变型mtDNA所占的比例与耳聋轻重程度相关(r=0.771,P=0.003);家系组患者中,突变型mtD-NA所占的比例亦与耳聋轻重程度相关(r=0.850,P=0.015)。结论突变型mtDNA占所有mtDNA的比例与耳聋的严重程度密切相关,是非综合征型耳聋临床表型多样性的分子基础。

Objective To study the correlation between the number of mtDNA copies containing mtDNA A1555G mutation and the deafness phenotype,and further elucidate the molecular genetic basis of the phenotype diversity of non-syndromic hearing loss.Methods Real time-amplification refractory mutation system-quantitative PCR(RT-ARMS-qPCR) was established to detect the number of mtDNA copies containing wild-type and mutant(1555(G)) mtDNA.Twelve sporadic cases and 7 familial cases were enrolled in this study and the correl...