散发性肥厚型心肌病β肌球蛋白重链及肌钙蛋白T基因突变的研究

目的研究β肌球蛋白重链(MYH7)及肌钙蛋白T(TNNT2)突变是否为散发性肥厚型心肌病(SHCM)患者的致病基因。方法对50例无血缘关系家族中仅1例患病且无一级亲属猝死史的SHCM患者及80例有一级亲属的SHCM患者进行MYH7及TNNT2扫描。提取所有DNA片段用PCR扩增后以双脱氧末端终止法测序。结果(1)50例SHCM患者中均未发现TNNT2基因突变。有1例MYH7突变,位于20号外显子上的T13659C突变(Ile736Thr);(2)80例家族成员中未发现MYH7及TNNT2基因突变。结论SHCM患者MYH7及TNNT2基因突变发生率低,可能不是SHCM的主要致病基因。

Mutations of the β-myosin heavy chain and troponin T genes in sporadic hypertrophic cardiomyopathy

Objective To study the mutations of beta-myosin heavy chain gene(MYH7)and troponin T(TNNT2) gene in patients with sporadic hypertrophic cardiomyopathy(SHCM).Methods Fifty SHCM patients without family history of HCM or sudden death in other first-generation relatives,and 80 family members of the SHCM patients were recruited in the study to screen disease-causing gene mutations of MYH7 and TNNT2.Deoxyribonucleic acid(DNA) samples were amplified by polymerase chain reaction(PCR),and PCR products were sequenced by dideoxy chain-termination method.Results(1)Of the 50 SHCM patients,only 1(2%) had MYH7 mutation,which showed T13659C mutation(Ile736Thr)located in exon 20.TNNT2 mutation was not identified in all SHCM patients.(2) No mutation of MYH7 and TNNT2 was identified in all family members.Conclusion Prevalence of mutations of MYH7 and TNNT2 is very low in SHCM patients in this study.It seems to be not the predominant disease-causing gene in patients with sporadic hypertrophic cardiomyopathy.