Kode et al. demonstrated in a murine model that activated β-catenin in osteoblasts stimulated the expression of the Notch ligand Jagged1 by these cells, with subsequent activation of Notch signaling in the leukemia-initiating long-term repopulating HSC progenitors, without changes in other BM hematopoietic stem and progenitor cell populations. This evidence concerns the gene JAG1 and leukemia.