Specifically, we: (1) hypothesize that SMYD2 is essential for the development of mesendoderm and several of its downstream organs (heart, kidney, liver, thymus, and ovaries) in part via its role in WNT signaling; (2) highlight the recently discovered role of SMYD2 in hematopoiesis and leukemias; and (3) suggest a possible role of SMYD2 in the migration of gonadotropin-releasing hormone (GnRH) neurons during the development of the vomeronasal organ (VNO). The gene discussed is SMYD2; the disease is leukemia.