[Mutations in beta myosin heavy chain gene: two mutations in Chinese with familial hypertrophic cardiomyopathy and the correlation between the genotype and phenotype].

OBJECTIVE: To study the disease-causing gene mutation in Chinese with hypertrophic cardiomyopathy (HCM), and to analyze the correlation between the genotype and phenotype.

METHODS: Samples of peripheral blood were collected from five Chinese patients with HCM in whose families at least 2 HCM patients existed. The exon in the functional regions of the beta myosin heavy chain gene (beta-MHC) were amplified with PCR and the products were sequenced. The relation between the genotype and phenotype was analyzed.

RESULTS: Two mutations were first identified. Eighty controls were normal in the genetic test.

CONCLUSION: beta-MHC may be the main disease-causing gene. Two mutations have different phenotypes. In one family, the identical mutation has different phenotypes and prognoses. The heterogeneity of phenotype suggests that multiple factors be involved in the pathogenesis.