Mononuclear cells were isolated from bone marrow (BM) aspirates or peripheral blood cells at diagnosis and CD10+CD19+ cells were isolated from human cord blood WGBS libraries were carried out using the TruSeq DNA Sample Prep Kit v2 (Illumina) with an added bisulfite conversion step. ChIP-seq libraries were carried out using the Paired-End DNA Sample Prep Kit V1 (Illumina; PE-102-1001)