Whatever the fraction injected in the mice (total CD34+ cells or sorted HSC, MPP, and LMPP), direct sequencing of human engrafted CD45+ cells and CFC analysis out of the mice revealed that the clonal architecture of the native JMML sample (whether at diagnosis or relapse) was maintained in mice (Fig. 4b and Supplementary Table S6). Here, CD34 is linked to juvenile myelomonocytic leukemia.