GSTM1 and anemia (phenotype): Initial full blood count and serum iron studies (Table 1) showed a profound hypochromic microcytic anemia (Hb 69 g/L, MCV 56 fL), normal erythrocyte sedimentation rates (7.0 mm/hour), an increased red cell distribution width (22.0%), severe hypoferremia (<2.0 μmol/L) with very low transferrin saturations (0.03%) and normal serum ferritin levels (32.0 μg/L).