Her iron profile (Table 1) is suggestive of iron deficiency and she started to show a response to intravenous iron supplementation. The total infused dose of iron was 1635 mg in the form of ferric carboxymaltose. At day seven, the reticulocyte count was 3.40%. After four weeks of iron transfusion, her Hb was 9.4 g/dL, TLC was 5432/cumm, and platelet was 210000/cumm. The gene discussed is GSTM1; the disease is Iron deficiency anemia.