Now, we know that most cardiomyopathy cases are heritable [3] and several mutations in cardiac muscle genes, such as myosin, tropomyosin, cardiac troponin T (cTnT), and cardiac troponin I (cTnI) have been identified to be associated with cardiomyopathies [4–7]. Here, TNNI3 is linked to cardiomyopathy.