We have analyzed the exons 13, 16, 21 and 23 of cardiac myosin heavy chain gene in 32 Chinese patients with hypertrophic cardiomyopathy by using PCR-single strand conformation polymorphism (PCR-SSCP) procedure. The re...We have analyzed the exons 13, 16, 21 and 23 of cardiac myosin heavy chain gene in 32 Chinese patients with hypertrophic cardiomyopathy by using PCR-single strand conformation polymorphism (PCR-SSCP) procedure. The result showed an altered SSCP of the exon 13 in one patient. Sequencing analysis revealed that the patient had a G to T transversion in the codon 383, resulting in the substitution of Lys by Asn. Beacause the missense mutation was found at the residue highly conserved through species evolution, this mutation is likely, to be the cause of hypertrophic cardiomyopathy in this patient. This is the first report of a mutant cardiac β-MHC gene in the Chinese population. Also, it is a novel missense mutation of the cardiac β-MHC gene.展开更多
Background Hypertrophic cardiomyopathy （HCM） is a form of cardiomyopathy with an autosomal dominant inherited disease, which is caused by mutations in at least one of the sarcomeric protein genes. Mutations in the b...Background Hypertrophic cardiomyopathy （HCM） is a form of cardiomyopathy with an autosomal dominant inherited disease, which is caused by mutations in at least one of the sarcomeric protein genes. Mutations in the beta-myosin heavy chain （β-MHC） are the most common cause of HCM. This study was to reveal the disease-causing gene mutations in Chinese population with HCM, and to analyze the correlation between the genotype and phenotype. Methods The exons 3 to 26 of MYH7 were amplified by PCR, and the PCR products were sequenced in five non-kin HCM patients. A 17-year-old patient was detected to be an Arg723Gly mutation carrier. Then his family was gene-screened, and the correlation between genotype and phenotype was analyzed. Results The mutation of Arg723Gly in a Chinese family with HCM was detected for the first time. With a C-G transversion in nucleotide 13 619 of the MYH7 gene, located at the essential light chain interacting region in S1, the replacement of arginine by glycine took place at amino acid residue 723. A two-dimensional echocardiogram showed moderate asymmetrical septal hypertrophy with left atria enlargement. There was no obstruction in the left ventricular outflow tract. In his family, a total of 13 individuals were diagnosed HCM and 5 of them were dead of congestive heart failure at a mean age of 66-year-old. Eight living members were all detected to carry the mutation, in which 3 developed progressive heart failure. Moreover, the heart function of the people evidently deteriorates when their age are older than 50. The mutation and the disease show co-separated. Conclusion The Arg723Gly mutation is a malignant type. In Chinese the mutation has the similar characters to the former report but has low degree malignant.展开更多
目的观察1个中国汉族肥厚型心肌病(HCM)家系的基因突变类型,并探讨其对临床表型的影响。方法选择1个中国汉族HCM家系,家系成员共13例,其中5例确诊为HCM。采用新一代高通量测序技术检测先证者外周血44个心肌病靶基因,结果显示其存在β肌...目的观察1个中国汉族肥厚型心肌病(HCM)家系的基因突变类型,并探讨其对临床表型的影响。方法选择1个中国汉族HCM家系,家系成员共13例,其中5例确诊为HCM。采用新一代高通量测序技术检测先证者外周血44个心肌病靶基因,结果显示其存在β肌球蛋白重链7(MYH7)基因18号外显子Arg663His突变及肌钙蛋白I3(TNNI3)基因7号外显子c.470C>T突变。采用双脱氧末端终止法测序检测该家系中其他成员上述两个基因的突变情况,分析不同MYH7、TNNI3基因突变的HCM患者的临床表现。结果先证者与其妹妹均存在MYH7基因18号外显子Arg663His及TNNI3基因7号外显子c.470C>T双突变,HCM发病年龄分别为2、1岁;心电图均示异常Q波,ST-T改变,左室高电压;超声心动图均示左房增大,室间隔中段以上最厚处分别为25、23 mm,SAM征阳性,左室流出道压差分别为80、68 mm Hg。先证者的母亲、二舅及外公仅MYH7基因18号外显子Arg663His突变,HCM发病年龄分别为21、19、30岁;心电图均示ST-T改变,左室高电压;超声心动图均示室间隔增厚,最厚处分别为16、18、18 mm,SAM征阴性,无左室流出道梗阻。先证者表弟仅MYH7基因18号外显子Arg663His突变,临床无明显症状,心电图及超声心动图检查无异常。结论该汉族HCM家系TNNI3基因发生从头突变,MYH7基因突变由遗传而来;MYH7与TNNI3基因双突变者HCM发病时间早、临床症状严重、预后较差。展开更多
文摘We have analyzed the exons 13, 16, 21 and 23 of cardiac myosin heavy chain gene in 32 Chinese patients with hypertrophic cardiomyopathy by using PCR-single strand conformation polymorphism (PCR-SSCP) procedure. The result showed an altered SSCP of the exon 13 in one patient. Sequencing analysis revealed that the patient had a G to T transversion in the codon 383, resulting in the substitution of Lys by Asn. Beacause the missense mutation was found at the residue highly conserved through species evolution, this mutation is likely, to be the cause of hypertrophic cardiomyopathy in this patient. This is the first report of a mutant cardiac β-MHC gene in the Chinese population. Also, it is a novel missense mutation of the cardiac β-MHC gene.
文摘Background Hypertrophic cardiomyopathy （HCM） is a form of cardiomyopathy with an autosomal dominant inherited disease, which is caused by mutations in at least one of the sarcomeric protein genes. Mutations in the beta-myosin heavy chain （β-MHC） are the most common cause of HCM. This study was to reveal the disease-causing gene mutations in Chinese population with HCM, and to analyze the correlation between the genotype and phenotype. Methods The exons 3 to 26 of MYH7 were amplified by PCR, and the PCR products were sequenced in five non-kin HCM patients. A 17-year-old patient was detected to be an Arg723Gly mutation carrier. Then his family was gene-screened, and the correlation between genotype and phenotype was analyzed. Results The mutation of Arg723Gly in a Chinese family with HCM was detected for the first time. With a C-G transversion in nucleotide 13 619 of the MYH7 gene, located at the essential light chain interacting region in S1, the replacement of arginine by glycine took place at amino acid residue 723. A two-dimensional echocardiogram showed moderate asymmetrical septal hypertrophy with left atria enlargement. There was no obstruction in the left ventricular outflow tract. In his family, a total of 13 individuals were diagnosed HCM and 5 of them were dead of congestive heart failure at a mean age of 66-year-old. Eight living members were all detected to carry the mutation, in which 3 developed progressive heart failure. Moreover, the heart function of the people evidently deteriorates when their age are older than 50. The mutation and the disease show co-separated. Conclusion The Arg723Gly mutation is a malignant type. In Chinese the mutation has the similar characters to the former report but has low degree malignant.
文摘目的观察1个中国汉族肥厚型心肌病(HCM)家系的基因突变类型,并探讨其对临床表型的影响。方法选择1个中国汉族HCM家系,家系成员共13例,其中5例确诊为HCM。采用新一代高通量测序技术检测先证者外周血44个心肌病靶基因,结果显示其存在β肌球蛋白重链7(MYH7)基因18号外显子Arg663His突变及肌钙蛋白I3(TNNI3)基因7号外显子c.470C>T突变。采用双脱氧末端终止法测序检测该家系中其他成员上述两个基因的突变情况,分析不同MYH7、TNNI3基因突变的HCM患者的临床表现。结果先证者与其妹妹均存在MYH7基因18号外显子Arg663His及TNNI3基因7号外显子c.470C>T双突变,HCM发病年龄分别为2、1岁;心电图均示异常Q波,ST-T改变,左室高电压;超声心动图均示左房增大,室间隔中段以上最厚处分别为25、23 mm,SAM征阳性,左室流出道压差分别为80、68 mm Hg。先证者的母亲、二舅及外公仅MYH7基因18号外显子Arg663His突变,HCM发病年龄分别为21、19、30岁;心电图均示ST-T改变,左室高电压;超声心动图均示室间隔增厚,最厚处分别为16、18、18 mm,SAM征阴性,无左室流出道梗阻。先证者表弟仅MYH7基因18号外显子Arg663His突变,临床无明显症状,心电图及超声心动图检查无异常。结论该汉族HCM家系TNNI3基因发生从头突变,MYH7基因突变由遗传而来;MYH7与TNNI3基因双突变者HCM发病时间早、临床症状严重、预后较差。
