ANKRD37 and Iron deficiency anemia: It has been recently shown that hypoxia is a key molecular signal for iron metabolism.11 Iron deficiency causes cellular hypoxia via increasing protein stability of hypoxia inducible factor 1α (HIF1α) and HIF2α transcription factors due to inactivation of HIF prolyl-hydroxylases (PHDs), but available iron can reduce stability of HIF1α and HIF2α by activation of PHD enzymes.27Ankrd37 is one of the most sensitive genes that is regulated by hypoxia.16,18 Thus, Ankrd37 was used as a genetic marker for hypoxia in the current study.