Thrombocythemia 2

Familial thrombocytosis in which the cause of the disease is a mutation in the MPL gene that produces constitutive activation of the thrombopoietin receptor, leading to excessive megakaryocyte proliferation and elevated platelet counts. Affected individuals exhibit sustained thrombocythemia, which may be accompanied by thrombotic or hemorrhagic complications and, in rare cases, leukemic transformation.