中文摘要：

目的：研究中国人心肌肌球蛋A结合蛋白C基因（MYBPC3）突变，分析其基因型与表型的关系。方法：对一个肥厚型心肌病家系成员进行MYBPC3突变筛查，利用聚合酶链反应（PcR）扩增其功能区外显子片段，双脱氧末段终止法测序。表型分析包括临床特点、二维心脏超声及组织多普勒（TDI）。结果：在此家系中，同时发现MYBPC3基因C．2526C〉G和C．2971G〉A两个位点的突变，而正常对照组同一位点未见异常。此家系共27人，其中4人患病，7人携带，C．2526C〉G位于第25号外显子，编码蛋白由谷氨酸变为终止子，C．2971G〉A位于第28号外显子，编码蛋白由缬氨酸变为蛋氨酸。4名患者均表现为室问隔中部肥厚，2名双突变患者同时合并心尖部肥厚，舒张功能均明显受损，而7名携带者中有3名出现局部心肌舒张功能的异常。结论：MYBPC3基因双位点突变可能会导致其肥厚范围扩大，心肌受损程度加重。MYBPC3基因突变可能直接影响左室舒张功能。

英文摘要：

Objective： To determine the associated mutations in myosin-binding protein C3 （MYBPC3） in Chinese patients with family hypertrophic cardiomyopathy （FHCM） and to analyze the genotype and phenotype correlation. Methods： One family with 27 family members affected with FHCM was chosen for the study. The full encoding exons of MYBPC3 were amplified with PCR and the products were sequenced. The clinical data and echocardiography were collected. Results： Two missense mutations in the family were identified： one was C.2526C〉G mutation which caused a tyrosine （Tyr） to terminator exchange at amino acid residue 842 and the other wasC.2971G〉A mutation which resulted in a valine （Val） to methionine （Met） exchange at amino acid residue 991. Four patients in the family suffered from HCM with asymmetric interventricular septal hypertrophy. The left ventricular diastolic function was significantly reduced. Signs of regional diastolic abnormalities occurred in some mutation carriers. Conclusion： Severe hypertrophy and diastolic dysfunction of the disease are compatible with the presence of double mutations in MYBPC3. Signs of regional diastolic abnormalities suggest a primary response to the mutations of MYBPC3 expression.