In a human clinical setting, overexpression of NF-E2 was first identified in polycythemia vera (PV) patients, and later extended to all myeloproliferative neoplasms (Goerttler et al., 2005, Wang et al., 2010), disorders characterized by overproduction of erythroid cells and often megakaryocytes and platelets. The gene discussed is NFE2; the disease is acquired polycythemia vera.