A troponin T mutation that causes infantile restrictive cardiomyopathy increases Ca2+ sensitivity of force development and impairs the inhibitory properties of troponin.
Our results (i) confirm that genetic backgrounds of hypertrophic cardiomyopathy and restrictive cardiomyopathy overlap and (ii) indicate that TNNC1 is a likely novel gene for autosomal recessive restrictive cardiomyopathy.