Jarid1b is not required for steady-state hematopoiesis. (A) Expression of Jarid1b in hematopoietic populations.18 (B) qRT-PCR of Jarid1b expression in HSCs, MPPs (LSKCD34+), and MPs (Lineage–Sca1–ckit+). (C) Image of Jarid1b WT and KO spleen. Bar represents 1 cm. (D) Weight of Jarid1b control (WT or heterozygote) and KO spleens. FACS analysis of spleen (E) and thymus (F) from 8-week-old male Jarid1b control or KO mice. Blood count analysis of Jarid1b control and KO PB for leukocytes (G), lymphocytes (H), and erythrocytes (I). (J) FACS analysis of hematopoietic populations within the BM of Jarid1b KO mice. Error ± standard deviation, n = 5 mice per group; ***P < .001. (K) Frequency of HSCs, MPP1 (LSK34+Flk2−), and MPP2 (LSKCD34+Flk2+) within the BM LSK compartment. (L) Frequency of CMPs (LSKCD34+FcγRαmid), GMPs (LSKCD34+FcγRαhi), and MEPs (LSKCD34−FcγRα−) of the BM MP compartment. (M) Frequency of CLPs (Lineage−Flk2hiIL7Rα+) within live BM. Error ± standard deviation; n = 3. B cell, IgM+B220+; CLP, common lymphoid progenitor; CMP, common myeloid progenitor; Ctl, control; EP, erythroid progenitor (Ter119+CD71+); FACS, fluorescence-activated cell sorter; GMP, granulocyte-macrophage progenitor; Gran, granulocyte (Mac1+Gr1+); LSK, Lineage–Sca1+cKit+; MEP, megakaryocyte-erythroid progenitor; MP, myeloid progenitor; qRT-PCR, quantitative reverse-transcription polymerase chain reaction; SP, single positive; WT, wild-type.