Dnmt3a loss induces MF in Jak2^VFMPNs. (A) Experimental design, in vivo transplantation of Jak2^VF LSKs transduced with lentivirus coding Cas9 coupled to a GFP reporter plus or minus sgRNA targeting Dnmt3a. (B-F) Left panels, Shown, respectively, are platelet number, hemoglobin concentration, leukocyte number, hematocrit, and GFP (edited cells) kinetic (over 32 weeks) from blood of recipient mice transplanted with Jak2^VF-Cas9 and Jak2^VF-Dnmt3a-Cas9 LSKs. Right panel, Dot plots show, respectively, platelet numbers, hemoglobin concentration, leukocyte number, hematocrit, and GFP expression at week 8 and week 32 (n ≥ 5 per group, per experiment; data represent pool of 2 experiments; mean ± standard error of the mean [SEM]). P values were calculated using the unpaired Student t test: *P < .05, **P < .01, ***P < .001. (G) Kaplan-Meier survival curve of WT recipient mice transplanted with Jak2^VF-Cas9 and Jak2^VF-Dnmt3a-Cas9 LSK cells over 32 weeks (n ≥ 5; per experiment, data represent pool of 2 experiments). Jak2^VF-Cas9, Jak2^VF-Dnmt3a-Cas9. (H) Representative flow cytometry gating strategy for erythroid progenitor cell populations. Left panel (black), Jak2^VF-Cas9; right panel (blue), Jak2^VF-Dnmt3a-Cas9 bone marrow (BM) cells. Percentage of erythroid progenitor populations at week 32 in Jak2^VF-Cas9 and Jak2^VF-Dnmt3a-Cas9 BM cells (n = 5 mice, mean ± SEM). P values were calculated using the unpaired Student t test. *P < .05, ***P < .001.