Therefore, the ongoing trials, the Evaluating the Efficacy of Erythropoietin and Intravenous Iron on Transfusion Requirements in Patients Undergoing Cardiac Surgery (IRCT20190121042447N1) and the Intravenous Iron for Treatment of Anemia Before Cardiac Surgery (NCT02632760) [1] are anticipated to elucidate the impact of preoperative IV iron for anemic patients undergoing cardiac surgery. The gene discussed is EPO; the disease is anemia (phenotype).