GATA4 and familial dilated cardiomyopathy: PROX1 can directly repress the expression offast-twitch skeletal muscle genes (e.g., troponin T3, troponin I2, and myosin lightchain 1) at transcriptional level (5).Cardiac-specific knockout of PROX1 causes overexpression of fast-twitchgenes, and thus leads to a change from slow-twitch to fast-twitch muscle phenotype, aswell as postnatal development of fatal DCM (5).Moreover, GATA4 is one of the cardiac TFs crucial for normalcardiogenesis, and its heterozygous mutations, like p.V39L, p.P226Q and p.T279S, havebeen found in sporadic DCM patients (6).