GSTM1 and anemia (phenotype): When compared to their wild-type (WT) littermates, peripheral blood counts revealed a marked anemia in Mcph1−/− mice with a 1.6-fold reduction in hemoglobinemia (Hb) (90 vs 147 g/L in KO and WT mice, respectively; p < 0.0001) due to a drastic reduction of mature red blood cell (RBC) (2.7-fold reduction, 1.06 vs 2.82 × 1012/L in KO and WT mice, respectively; p < 0.0001) (Fig. 1B,C).