GSTM1 and anemia (phenotype): Of those, 57 (51.8%) had mild anemia (134 < Hb ≤ 90 g/L in males, 117 < Hb ≤ 90 g/L in females), 46 (41.8%) moderate anemia (90 < Hb ≤ 60 g/L), and 7 (6.4%) severe anemia (Hb < 60 g/L).