Xenotransplantation of cells from ten JMML samples at diagnosis and two JMML samples at relapse was thus performed in parallel in two immunocompromised mouse strains NSG mice and NSG-S mice (also called NSG-SGM3), which is humanized to express the cytokines GM-CSF, SCF and IL-3 (Supplementary Table S1). This evidence concerns the gene IL3 and juvenile myelomonocytic leukemia.