Haploinsufficiency of c-Myc leads to ineffective hematopoiesis. (A) Absolute number of WBCs, neutrophils (NEs), LYs, monocytes (MOs), eosinophils (EOs), and basophils (BAs) in PB from c-Myc^fl/+ (WT) and c-Myc^fl/+ Mx1-Cre (HET) mice 4 months after pIpC injection (n = 7-8). (B) PCR analysis of the deletion of c-Myc (Mut band) and WT c-Myc allele among genomic DNA in BM cells from WT and HET mice 4 months after pIpC injection. (C) Total BM cells in WT and HET mice 4 months after pIpC injection (n = 6-12). (D-G) Number of myeloid cells (Mac⁺Gr1⁺) (D), MOs (Mac⁺Gr1^low) (E), and B cells (B220⁺) (F) in BM and ratio of CD4⁺CD8⁺ cells in the thymus (G) from WT and HET mice 4 months after pIpC injection (n = 7-13). Number of HSCs (I) and HPCs (J) in BM from WT and HET mice 4 months after pIpC injection. Gating strategy is shown in panel H; HSC: Lin⁻c-Kit⁺Sca1⁺ CD48⁻CD150⁺; HPC: Lin⁻c-Kit⁺Sca1⁻ (n = 10-13). Number of GMPs (L), CMPs (M), and MEPs (N) in BM from WT and HET mice 4 months after pIpC injection. (K) Gating strategy for GMPs: Lin⁻c-Kit⁺Sca1⁻ CD16/32⁺CD34⁺; CMPs: Lin⁻c-Kit⁺Sca1⁻ CD16/32⁻CD34⁺; and MEPs: Lin⁻c-Kit⁺Sca1⁻ CD16/32⁻CD34⁻ (n = 8-13). *P < .05; **P < .01; NS nonsignificant, by Student t test.