GSTM1 and anemia (phenotype): Among β-thalassemia genes, the anemia rate and the Hb and MCH levels caused by βIVS–II–654(C>T) (β+) were similar to those of common β0-thalassemia genes (βCD41/42 (–TTCT), βCD17(A>T), and βCD71/72(+A)) (P > 0.05).