GSTM1 and anemia (phenotype): Additionally, β-thalassaemia patients with combined mutations, such as IVS 1-2 (T>C) (β+) and Cd 26 (GAG>AAG) HbE (βE) and Cd 41/42 (-TTCT) (β0), IVS 1-5 (G>C) (β+), and codon 26 (G>A) HbE (βE), have severe microcytic hypochromic anaemia (Hb: 65 g/dL; MCV:72.1.3 fl) with significant thrombocytosis (545 × 109/L) and leukocytosis (11.7 × 109/L) as compared to patients with other mutations.