More interestingly, parameters suggestive of stronger myeloproliferation and more aggressive disease, such as MF phenotype, JAK2 mutation, higher total MPN SAF score, lower performance status, thrombosis history, lower hemoglobin and hematocrit values, and higher RDW, were more frequent in MPN patients with sOA. Here, JAK2 is linked to myeloproliferative neoplasm.