Admission blood tests revealed pancytopenia (Hb 82 g/l, WCC 1.5 × 109/L, Plt 84 × 109/L, and neutrophils 1.0 × 109/L), macrocytosis (MCV 114 fL), normal reticulocyte count, and raised CRP (30 mg/l) with normal kidney and liver function tests. Here, GSTM1 is linked to Pancytopenia.