MYH7 is a gene encoding a myosin heavy chain beta (MHC-β) isoform (slow twitch) expressed primarily in the heart. Changes in the relative abundance of MHC-β and MHC-α (MYH6, the fast isoform of cardiac myosin heavy chain) correlate with the contractile velocity of cardiac muscle. In early fetal development, MHC-β is predominately expressed in the ventricles, while MHC-α is predominantly expressed in the atria. In healthy adult hearts, MHC-α is predominantly expresse… (More on Myh7)