[Genetic heterogeneity of myosin heavy chain 7 gene G823E mutation in familial hypertrophic cardiomyopathy in Chinese].

To study the disease-causing gene mutations in familial hypertrophic cardiomyopathy (HCM) in Chinese and to reveal the relationship between the genotype and the phenotype.Peripheral blood samples were collected from 12 members of a HCM family, and 120 healthy volunteers in China. PCR and double deoxygenation chain termination method were used to analyze the cardiac troponin T gene (TNNT2), beta-myosin heavy chain gene (MYH7) gene and myosin binding protein C gene (MYBPC3) and to detect mutations.Mutation G14452A was identified in exon 22 of MYH7 gene in 4 family members, causing the conversion of glycine (G) into glutamic acid (E). The onset ages and clinical manifestations of the family members carrying the mutation G823E, including 2 patients (the proband, male, with the onset age of 51, and his 26-year-old second son with the onset age of 20), and 2 carriers (his 31-year-old elder son and 29-year-old elder daughter), presented significant individual differences.The G823E mutation of MYH7 gene is the causal mutation of familial HCM. The heterogeneity of phenotypes suggests that multiple factors may be involved in the pathogenesis of HCM.