MPNs have been categorized by the WHO as: chronic myeloid leukaemia (CML), polycythaemia vera (PV), primary myelofibrosis(PMF) and essential thrombocythemia (ET) and are characterized by the presence of the BCR-ABL gene, JAK2, MPL or CALR mutations, excessive erythrocyte production, fibrotic bone marrow degeneration, and excessive megakaryocyte lineage proliferation, respectively (3). This evidence concerns the gene JAK2 and acquired polycythemia vera.