中国汉族家族性肥厚型心肌病中首次发现MYH7基因Ile736Thr突变

目的 研究中国汉族人家族性肥厚型心肌病的致病基因突变位点,分析基因型与临床表型的相互关系。方法 对3个患家族性肥厚型心肌病家系的先证者进行β肌球蛋白重链基因(MYH7)扫描,聚合酶链式反应扩增其功能区外显子片断,双脱氧末端终止法测序。对阳性结果者进行家系中其他成员的筛查,全部进行β肌球蛋白重链基因目的片段的筛查,并分析家系中患者的临床表型特点。结果 在1个家系中发现Ile736Thr杂合突变,而正常对照组同一位置未见异常,Ile736Thr为我国患者中首次发现。结论 β肌球蛋白重链基因可能为我国家族性肥厚型心肌病的主要致病基因之一。Ile736Thr所致肥厚型心肌病其临床症状出现较晚,但进展快,易发生心力衰竭,预后较差。

Mutations in beta myosin heavy chain gene:one mutation Ile736Thr identified firstly in Chinese with hypertrophic cardiomyopathy and the correlation between their genotype and phenotype

Objective To study the disease-causing gene mutation in Chinese with hypertrophic cardiomyopathy (HCM) , and to analyze the correlation between their genotype and phenotype. Method Three families suffering from HCM were chosen for the study. The exon in the functional regions of the beta myosin heavy chain gene were amplified with PCR and the products were sequenced. The relation between the genotype and phenotype was analyzed. Results One mutation was identified in exon 20 in one family. The mutation of Ile736Thr was firstly identified in Chinese. The results of genetic test were normal in eighty controls. Conclusions Beta myosin heavy chain gene might be one of the main disease-causing genes in Chinese with familial HCM. The symptoms occur later and prognosis seems poor in this kind of HCM. In the same family, the identical mutation may have different phenotypes.