GSTM1 and anemia (phenotype): Full blood examination of adult CISH KO mice revealed no significant difference in red blood cell (RBC) number or mean cell hemoglobin (MCH) compared to CISH WT mice, but subtle alterations in other red blood cell parameters were observed, including a decreased hemoglobin (Hb), hematocrit (HCT) and mean cell hemoglobin content (MCHC), but increased mean cell volume (MCV) (Table 1), consistent with mild macrocytic anemia.