FLT3-ITD as well as FLT3-TKD stimulates the various downstream signaling pathways that are normally activated by ligand-stimulated FLT3, such as the PI3K/Akt/mTOR and MEK/ERK pathways, thus leading to survival and proliferation of model hematopoietic cell lines or causing myeloproliferative disorders in various murine models [1–3]. The gene discussed is FLT3; the disease is myeloproliferative disorder.