Chromatin 500.000 FACS sorted LSKs or GMPs was incubated with antibodies recognizing C/EBPa. For histone modification 100.000 FACS sorted cells were used for ChIP. The antibody-bound chromatin was captured with Protein-A sepharose beads, washed, de-cross-linked and precipitated. DNA was extracted using standard phenol-chloroform extraction Precipitated DNA were mixed with 2 ng E. Coli DNA and amplified using NEB Next ChIP-seq sample prep reagent set 1 (New England Biolabs) according to manufacturers protocol.