Competitive and noncompetitive transplantation assay. (A) Schematic depiction of the competitive transplantation assay. Vav-Cre–only and Vav-Cre–positive Asxl1-MT^fl/fl mice are positive for CD45.2, whereas WT competitor cells are positive for CD45.1. Unfractionated BM cells (0.5 × 10⁶) from CD45.2 control (Vav-Cre only) or KI (Vav-Cre–positive Asxl1-MT^fl/fl) and CD45.1 WT competitor (mixed 1:1) were transplanted into lethally irradiated (9.5 Gy) recipients (n = 7 mice per group). We followed up the chimerism (CD45.2⁺) and CD11b/B220/CD3–positive cells in the PB every 4 wk. (B) Percentage of donor chimerism in the PB after competitive repopulation assay (n = 7 mice per group). (C) The donor chimerism (CD45.2⁺) of each stem/progenitor fraction was evaluated by FACS. ST, short term. (D) The absolute number of CD45.2⁺ whole BM, LSK, LT-HSCs, and MPPs in each group (n = 7 each). (E) Percentage of donor chimerism in the PB 4–22 wk after noncompetitive repopulation assay. Unfractionated BM cells (10⁶) from control (Vav-Cre–negative Asxl1-MT^fl/wt) or KI (Vav-Cre–positive Asxl1-MT^fl/wt) mice were used as donor cells (n = 6 in control and n = 5 in KI). (F) Related to E; shows the proportion of donor chimerism and each lineage in the PB at 4 wk after transplantation in a noncompetitive fashion. The cells derived from Vav-cre Asxl1-MT^fl/wt mice were identified by CD45.2 positivity. Data are presented as mean ± SEM. *, P < 0.05; **, P < 0.01; ***, P < 0.001; ****, P < 0.0001 (Student’s t test). All of the control mice used in the transplantation assay were age matched. BMT, bone marrow transplantation.