Total bone marrow cells were isolated from long bones (femur and tibia; 5 mice per experimental replicate) following by treatment with the ACK lysis buffer (0.15 M NH4Cl, 10 mM KHCO3, 0.1 mM EDTA [pH 7.2]) to remove red blood cells. An sorting of FACS-based analysis of lineage-/Sca1+/c-Kit+ (LSK) cells was carried out using a FACSAria II machine (UNC flow core) using the already defined protocol. ATAC-seq was carried out utilizing the Epicentre Tn5 transposome and Illuminia kit according to standard manufacturer's manuals.