Familial hypertrophic cardiomyopathy has been associated with several mutations in the
gene encoding human cardiac troponin I (HCTnI). A missense mutation in the inhibitory
region of TnI replaces an arginine residue at position 145 with a glycine and cosegregates
with the disease. Results from several assays indicate that the inhibitory function of HCTnI
R145G is significantly reduced. When HCTnI R145G was incorporated into whole troponin,
Tn R145G (HCTnT· HCTnI R145G· HCTnC), only partial inhibition of the actin-tropomyosin …