Prothrombin G20210A

It increases the risk of blood clots including from deep vein thrombosis, and of pulmonary embolism.

[3] The variant causes elevated plasma prothrombin levels (hyperprothrombinemia),[4] possibly due to increased pre-mRNA stability.

[8] The mutation increases the risk of developing deep vein thrombosis,[9] which can cause pain and swelling, and sometimes post-thrombotic syndrome, ulcers, or pulmonary embolism.

[10] Most individuals do not require treatment but do need to be cautious during periods when the possibility of blood clotting are increased; for example, during pregnancy, after surgery, or during long flights.

[14] In those who develop venous thromboembolism, the results of thrombophilia tests (wherein the variant can be detected) rarely play a role in the length of treatment.

[18] Patients with the prothrombin G20210A mutation who have not had a thromboembolic event are generally not treated with routine anticoagulation.

[19] This is because the combination of genetic predisposition (high baseline prothrombin levels) and the additional pro-coagulant influence of oral contraceptives alters the hemostatic balance of fibrinolysis to trigger thrombosis.