Runx1^R188Q/+ BM hematopoietic progenitor cells outcompete WT cells in BCRAs. (A-D) Contribution of donor (test/competitor: WT/WT in blue, Runx1^R188Q/+ /WT in red) HSPCs, including LKS+ (A), LT-, ST-HSCs and MPPs (B), LKS- (C), and committed progenitor cells (CMPs, GMPs, and megakaryocytic-erythroid progenitors (MEPs), D). (E) estimation of total BM cells. (F-J) Contribution of donor (test/competitor) cells to committed progenitor cells in BM, including lineage-negative (Lin⁻) cells (F), neutrophil- (G) and monocyte-progenitors (H), B cells (I) and T cells (J). ∗P < .05, ∗∗P < .005.