Pardanani et al. [7] screened MPL mutations in 1182 patients with MPN (290 with PMF, 242 with PV, 318 with ET) and other myeloid disorders (88 with myelodysplastic syndrome, 118 with CML, 126 with acute myeloid leukemia), regardless of JAK-2 V617F mutational status. Here, MPL is linked to acquired polycythemia vera.