THPO

Essential thrombocythemia

Several mutations in the THPO gene have been found in people with essential thrombocythemia, a condition characterized by an increased number of platelets in the blood. Because platelets are the blood cells involved in blood clotting, abnormal clotting (thrombosis) is common in people with essential thrombocythemia.

THPO gene mutations are found in families with an inherited form of the condition called familial essential thrombocythemia. These mutations affect a region of the gene that usually blocks (inhibits) the production of the thrombopoietin protein (a process called translation). THPO gene mutations lead to increased translation of the protein. The excess protein can abnormally activate the thrombopoietin receptor and the signaling pathways, leading to overproduction of megakaryocytes and increased numbers of platelets. Excess platelets can cause thrombosis, which leads to many signs and symptoms of essential thrombocythemia.