Pathogenesis of Hypertrophic Cardiomyopathy is Mutation Rather Than Disease Specific: A Comparison of the Cardiac Troponin T E163R and R92Q Mouse Models.
To investigate mutations in the sarcomeric genes MYH7, MYBPC3 and TNNT2 in a cohort of HCM patients living in the extreme south of Brazil, and to evaluate genotype-phenotype associations.
Seven single nucleotide polymorphisms and haplotypes in MYBPH were investigated for hypertrophy modifying effects in 388 individuals (27 families), in which three unique South African HCM-causing founder mutations (p.R403W and pA797T in β-myosin heavy chain gene (MYH7) and p.R92W in the cardiac troponin T gene (TNNT2)) segregate.
Thirty-eight HCM index patients (mean age 60±16 years) underwent systematic mutation screening of eight sarcomeric genes: β-myosin heavy chain (MYH7), myosin-binding protein C (MYBPC3), troponin T (TNNT2), troponin I (TNNI3), myosin ventricular regulatory light chain 2 (MYL2), myosin ventricular essential light chain 1 (MYL3), α-tropomyosin (TPM1), and cardiac α-actin (ACTC), using direct DNA sequencing.
Effects of troponin T cardiomyopathy mutations on the calcium sensitivity of the regulated thin filament and the actomyosin cross-bridge kinetics of human β-cardiac myosin.
Direct gene sequencing of β-myosin heavy chain (MYH7), myosin binding protein-C (MYBPC3), and cardiac troponin T (TNNT2) was performed in 136 unrelated Chinese HC patients.Clinical evaluations were conducted.
Hypertrophic cardiomyopathy (HCM) is an autosomal dominant disorder resulting from mutations in genes for at least 15 various sarcomere-related proteins including cardiac β-myosin heavy chain, cardiac myosin-binding protein C, and cardiac troponin T. The troponin T gene (TNNT2) mutation has the third incidence of familial HCM, and the genotype-phenotype correlation of this gene still remains insufficient in Japanese familial HCM.