has material basis in germline mutation in MPL essential thrombocythemia thrombocythemia 2 https://github.com/monarch-initiative/mondo/issues/230 https://github.com/monarch-initiative/mondo/issues/4521 https://github.com/monarch-initiative/mondo/issues/9994 https://www.malacards.org/card/thrombocythemia_2 GARD:0024778 MPL familial thrombocytosis THCYT2 MONDO:0011173 MEDGEN:477629 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. UMLS:C3275998 familial thrombocytosis caused by mutation in MPL OMIM:601977 MPL-related thrombocythemia familial thrombocytosis