第二代测序技术在假肥大型肌营养不良基因诊断中的应用

Application of next-generation sequencing technology for genetic diagnosis of Duchenne muscular dystrophy

目的对假肥大型肌营养不良患者进行基因检测。方法采用目标区序列捕获及第2代高通量测序技术对6例假肥大型肌营养不良患者进行检测；采用第1代测序技术、多重连接依赖的探针扩增技术（multiplexligation-dependentprobeamplification，MLPA）对患者及其母亲的基因型进行验证。结果1例为第10和11外显子缺失，1例为第16和17外显子重复，4例为点突变。共发现10种变异：C．2776C〉T、c．5475delA、C．6391—6392delCA、IVS64＋1G〉A、12．2645A〉G、C．5244G〉A、C．7728T〉C、C．8729A〉T、C．8734A〉G和C．8810G〉A，前4种为可疑致病性变异，后6种为人群中的多态。其中3例为首次发现的新突变（IVS64＋1G〉A、C．6391—6392delCA（P．Q2131NfsX3）和P．Q926X（CAG〉TAG）。结论通过第2代测序技术可以在一个反应中准确检测出DMD基因的缺失、重复和点突变，具有一定的临床应用价值。

Objective To detect genetic causes of Duchenne muscular dystrophy（DMD）. Methods Next-generation sequencing was used to detect 6 DMD patients in whom no exonic deletions were detected by multiplex PCR. Sanger sequencing and multiplex ligation-dependent probe amplification were used to confirm the results. Results One case was found to have deletions of exons 10 and 11, 1 had exons 16 and 17 duplication, 4 cases have 8 point mutations including c. 2776C〉T, c. 5475delA,. c. 6391_6392delCA, IVS64＋lG〉A,c. 2645A〉G,c. 5244G〉A,c. 7728T〉C,c. 8729A〉T,c. 8734A〉G and c. 8810G〉A. The former 4 mutations are suspicious pathogenicity, the other 6 mutations are polymorphism in population. Three novel mutations （ IVS64 q- 1G 〉 A, c. 6391 _ 6392delCA （ p. Q2131 NfsX3 ） and p. Q926X （ CAG TAG） were not reported before. Conclusion Next-generation sequencing technology is a useful tool for the detection of deletion, duplication and point mutation, which is valuable for clinical application.