Calcineurin is a calcium/calmodulin-dependent serine/threonine phosphatase [14], which is an important signaling molecule that is expressed in skeletal muscles, and it regulates the muscle fiber type by interacting with NFAT (nuclear factor of activated T cells) [15, 16]. Myoz1 KO mice displayed markedly improved performance due to enhanced Calcineurin signaling [17]. Myoz2, similar to Myoz1, can regulate cardiac hypertrophy [18]. The gene discussed is MYOZ1; the disease is cardiac hypertrophy.