TNNT2 and familial dilated cardiomyopathy: Several hypotheses have been formulated to explain the diverging heart phenotypes in HCM versus DCM manifesting from specific mutations within the same protein like cTnT: (1) mutations directly affecting calcium sensitivity (Robinson et al., 2002, 2007), (2) mutations affecting EC coupling or Ca2+ homeostasis (Tardiff et al., 2015; Crocini et al., 2016), and (3) mutations interfering with the effect of posttranslational modifications on calcium sensitivity (Sfichi-Duke et al., 2010; Memo et al., 2013; Messer et al., 2016).