JAK2 and acquired polycythemia vera: Three weeks after transplantation, engraftment of Jak2+/+ and Jak2V617F/+ CD45.2+ cells in CD45.1 recipient mice was confirmed (Supplementary Fig. 7a) and a PV-like MPN phenotype developed in Jak2V617F/+, but not in Jak2+/+, recipient mice (Supplementary Fig. 7b–e).