RecruitingProcedureDetermination of the Clonality Profile in Myeloproliferative Neoplasms and Association With the Thrombotic Complications (CLOJAK)Myeloproliferative Neoplasms (MPN) are associated with an increased risk of thrombosis. Platelets, red blood cells (RBC), leukocytes and endothelial cells are involved in these complications. An association with the JAK2V617F allele burden assessed in leukocytes has also been suggested. In some patients the allele burden measured in platelets and red blood cells is higher than the one determined in leukocytes. Our project aims at associating the risk of thrombosis with the allele burden determined in the cell populations (platelets, red blood cells, granulocytes and endothelial cells) and identifying high-risk clonality profiles.