全外显子组测序发现一家族性扩张型心肌病致病基因

164复2学报（医学版）

Fudan Univ J Med Sci

2018 Mar.，45(2)

全外显子组测序发现一家族性扩张型心肌病致病基因

周年伟“2’54秦胜梅3’5i刘阳1，2’5赵维鹏w’5崔洁3’5

潘翠珍1>2’5陈瑞珍3,5王小林1>4,5舒先红w’54

C1上海市影像医学研究所上海200032; 2复旦大学附属中山医院心超室，3心内科，

4介入治疗科上海200032; 5上海市心血管病研究所上海200032)

【摘要】目的对一扩张型心肌病(dilated cardiomyopathy,DCM)家系行全基因组外显子测序以寻找该家系的 致病基因。方法收集在复旦大学附属中山医院就诊的一位DCM患者及其家系成员的临床资料，采集相关家 系成员外周血并抽提DNA,对该家系5名成员行全基因组外显子测序，寻找致病基因，用Sanger测序对家系其 他成员进行验证。结果通过对家系患者与正常人测序结果比对分析，同时经过多个生物数据库数据过滤，发 现LMiVA基因6号外显子上存在的杂合突变c.961 C>T (p.Arg321Ter)为该家系的可能致病基因突变。

LMiVA c.961 C>T无义突变导致LM NA编码蛋白质过程提前终止，相应蛋白质功能异常，进而导致该家系中 此突变基因的携带者出现心功能异常。结论本研究应用全基因组外显子测序从一DCM家系中发现其致病 基因及突变位点:LMNA c.%1C>T (p.Arg321Ter)，突变导致该家系相关成员心功能异常。此位点在汉族人 群中尚属首次报道。

【关键词】扩张型心肌病；基因突变；全外显子测序

【中图分类号】Q987 【文献标识码】 A doij 10. 3969/j. issn. 1672-8467. 2018. 02. 004

Identification of gene mutation associated with familial dilated

cardiomyopathy by whole-exome sequencing

ZH O U N i a n-w e i m，QIN Sheng-mei3,5A，LIU Yang1，2,5，Z H A O W ei-peng1，2,5，CUI Jie3,5，PA N Cui-zhen1，2,5，CHEN Rui-zhen3,5，W A N G Xiao-lin1，4,5，SH U Xian-hong1，2，^ C1Shanghai Institute o f Medical Imaging >Shanghai 200032, China；2 Department o f Echocardiography, 3Department o f Cardiology ^Department o f Interventional Radiology ,Zhongshan H ospita l,Fudan University , Shanghai 2Q0Q32,China; 5 Shanghai Institute o f Cardiovascular Disease，Shanghai 2QQ032,China )

【Abstract】Objective T o identify the disease-causing gene in a Chinese pedigree with familial dilated cardiomyopathy (DCM) by whole-exome sequencing. Methods After collecting the clinical data and extracting the whole blood genomic DNA of the 5 family members form a Chinese DCM pedigree, whole-exome sequencing was performed to search the causative genes. Familial co-segregation analysis among the pedigree was subsequently confirmed by traditional Sanger sequencing. Results We performed whole exome sequencing (W ES) on representative affected individuals and unaffected familial members from this pedigree. After comparison with variants identified in affected individuals and unaffected individuals, along with previously reported genetic mutations associated with DCM, we found that a heterozygous variant c. 961 〇T(p. Arg321Ter) in exon 6 of the LMNA gene in affected 国家自然科学基金（81371576)

^ZHOU Nian-wei and QIN Sheng-mei contributed equally to this work

^Corresponding author E-mail：shu. xianhong@zs-hospital. sh. cn

周年伟，等.全外显子组测序发现一家族性扩张型心肌病致病基因165

individuals matched the criteria to be the potential disease-causing gene, which was confirmed by Sanger sequencing. This stop-gain mutation leads to only a small part of LMNA-coding protein expressed, therefore we concluded that LMNA c. 961 〇T should be the causative mutation for this familial DCM case. Conclusions The nonsense mutation c. 961 〇T in gene LMNA identified by whole-exome sequencing might be the pathogenic mutation in this DCM pedigree.

【Key words】dilated cardiomyopathy; mutation；whole-exome sequencing

* This work was supported by the National Natural Science Foundation o f China (81371576).

扩张型心肌病（dilated cardiomyopathy，DCM)主要临床特征是左心室扩大，并伴有左心室收缩功 能受损，D CM患者中30%〜50%为家族性[1]。目前已确定有40多种基因与家族性D C M发病相 关[2]。随着高通量测序技术的进步，全外显子组测 序通过外显子捕获技术富集全基因组D N A编码序 列，借助二代测序技术进行高效测序分析，全面提供 全基因组外显子区域的序列信息，极大促进了遗传 性疾病的基因诊断[3]。相较于常规基因panel筛查 的方法，全基因组外显子测序大大增强了检测结果 的可靠性。故本研究应用二代测序技术对一 DCM 家系行全基因组外显子测序分析寻找其致病基因。

资料和方法

研究对象本研究对象为一安徽籍DCM家系 (图1)。先证者是一位43岁男性患者（H-7,图1)，反复心悸、晕厥来复旦大学附属中山医院就诊，初步

诊断为心律失常，房室传导阻滞。入院检查心电图 提示房颤，三度房室传导阻滞，左束支传导阻滞；超 声心动图提示左心房左心室增大伴左心室收缩功能 减退，左心室射血分数LVEF= 42%。该患者胸片 提示心脏扩大（图2);血清肌酸激酶和肌钙蛋白T 较正常值稍偏高，既往无高血压、冠心病及糖尿病病 史，该患者诊断为DCM，接受了相关药物治疗并植 入了起搏器。先证者的表哥图1)，46岁，2 年前被诊断为房颤，DCM，也接受了起搏器植入术。

一般临床资料收集该家系所有成员详细的临 床资料，包括体格检查、发病年龄、初发症状、血清肌 酸激酶、纽约心功能分级、常规心电图及超声心动 图，并根据需要行动态心电图检查。所有研究对象 签署知情同意书后，采集其外周血标本，按照试剂盒 说明书步骤提取基因组DNA。本研究获复旦大学 附属中山医院伦理委员会批准（2016-16B)，所有研 究对象都知情同意并签署知情同意书。

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1…V/- 789I11121314 1516 171819 Filled sym bols：Patients；Open sym bols：Unaffected subjects；Small squares within sym bols：Genotype( + )-phenotype ( _ ) ；Diagonal lines：Death； A rrow：Probands. The presence ( + ) or absence ( _ ) of the mutation is indicated for the genetically tested family members.

图1扩张型心肌病家系图

Fig 1 Family diagram o f dilated cardiomyopathy