Thrombocythemia 2, also known as thcyt2, is related to thrombocythemia 1 and qualitative platelet defect. An important gene associated with Thrombocythemia 2 is MPL (MPL Proto-Oncogene, Thrombopoietin Receptor). Affiliated tissues include bone marrow and bone, and related phenotypes are increased megakaryocyte count and thrombocytosis