GSTM1 and anemia: For the entire study sample (n = 57), Hb concentration increased from 9.2 ± 1.0 g/dL at T0 to 12.8 ± 1.0 at T60 (mean Hb increment: 3.6 ± 1.5 g/dL; p < 0.01) (Fig. 2A), and 81% of patients experienced correction of anemia (Hb ≥ 12 g/dL) (Fig. 2B).