Ezh2^Δ/Δ mice developed myelodysplastic disorders. (A) Kaplan-Meier survival curves of WT (n = 24) and Ezh2^Δ/Δ (n = 32) mice. These survival curves were generated from 3 independent experiments. (B) A pie graph showing the types of hematologic malignancies observed in Ezh2^Δ/Δ mice (n = 32) during a long observation period. (C) PB cell counts in Ezh2^Δ/Δ mice 9 to 12 months after the deletion of Ezh2. WBC, Hb, and Plt counts in the PB from WT (n = 24) and Ezh2^Δ/Δ MDS (n = 6), MDS/MPN (n = 17), and MDS/MPN_TC (n = 9) mice are plotted as dots and the mean values are indicated as bars. (D) Absolute numbers of total BM cells and LSK cells in a unilateral femur, and spleen weights and numbers of LSK cells in the spleen relative to WT are plotted as dots and mean values are indicated as bars (WT, n = 21; MDS, n = 6; MDS/MPN, n = 16; MDS/MPN_TC, n = 5). Statistical significance of difference was measured by unpaired 2-tailed Student t test or Mann-Whitney test when the variance was judged as significantly different by f test. *P < .05, **P < .01, ***P < .001. Hb, hemoglobin; ND, not determined; Plt, platelet; WBC, white blood cell.