一个CDH23基因新型复合杂合突变导致的耳聋家系分析

Identifications of the Novel Mutants on CDH23 Gene in a Family with Non-syndromic Hereditary Deafness

孙毅;葛雨彤;刘雅琳;韩庆亚;郑宏

1:山东省康复医院

摘要
目的 研究一个家系中2例非综合征型遗传性聋患者的致病原因。方法 收集该耳聋家系临床检查结果资料,采集静脉血后提取DNA,应用全外显子组测序技术分析可疑致病基因,并通过Sanger测序对变异进行验证。结果 该家系中2代5人,先证者(Ⅱ-2,9岁)和其弟弟(Ⅱ-3)均为迟发性感音神经性听力损失,患者父母听力正常。先证者弟弟(Ⅱ-3)携带相同突变位点。基因检测结果显示,先证者携带CDH23基因c.4762C>T(p.ARG1588TRP)和c.6604G>A(p.ASP2202ASN)。根据美国医学遗传学与基因组学学会(American College of Medical Genetics and Genomics, ACMG)遗传变异分类标准与指南分析显示,c.4762C>T和c.6604G>A位点均为致病突变。蛋白功能分析发现,变异后氨基酸改变造成蛋白结构发生改变,进而影响蛋白质功能。结论 CDH23基因c.4762C>T和c.6604G>A复合杂合突变位点组合很可能是该家系耳聋致病基因。
关键词
CDH23基因;遗传性聋;基因测序;突变检测
基金项目(Foundation):
作者
孙毅;葛雨彤;刘雅琳;韩庆亚;郑宏
参考文献

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