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Prothrombin (Factor II) 20210 Gene Mutation


Joel L. Moake

, MD, Baylor College of Medicine

Last review/revision Jan 2021 | Modified Sep 2022
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A genetic mutation causes increased plasma levels of prothrombin (factor II), predisposing to venous thrombosis.

Prothrombin (factor II) is a vitamin K-dependent precursor of thrombin, the terminal enzyme of the coagulation cascade (see figure Pathways in blood coagulation Pathways in blood coagulation Pathways in blood coagulation ). A single nucleotide mutation in one (or, less commonly, both) of the prothrombin genes at position 20210 results in increased plasma prothrombin levels (with potentially increased thrombin generation) and increases the risk of venous thromboembolism Deep Venous Thrombosis (DVT) Deep venous thrombosis (DVT) is clotting of blood in a deep vein of an extremity (usually calf or thigh) or the pelvis. DVT is the primary cause of pulmonary embolism. DVT results from conditions... read more Deep Venous Thrombosis (DVT) .

The prevalence of the mutation ranges from < 1% to 6.5%, depending on the population studied.

Pathways in blood coagulation

Pathways in blood coagulation

The diagnosis is made by genetic analysis of the prothrombin 20210 gene using blood samples.

Treatment of Prothrombin (Factor II) 20210 Gene Mutation

  • Anticoagulation

Anticoagulation with heparin or low molecular weight heparin, followed by warfarin, is used for venous thrombosis, or for prophylaxis in patients at increased thrombotic risk (eg, by immobilization, severe injury, or surgery).

It is probable, but not yet certain, that the direct oral anticoagulant (DOAC) inhibitors Treatment In healthy people, homeostatic balance exists between procoagulant (clotting) forces and anticoagulant and fibrinolytic forces. Numerous genetic, acquired, and environmental factors can tip... read more of either thrombin (dabigatran) or factor Xa (eg, rivaroxaban, apixaban) can be used in place of other anticoagulants for this disorder.

Drugs Mentioned In This Article

Drug Name Select Trade
Recothrom, Thrombi-Gel , Thrombin-JMI, Thrombin-JMI Epistaxis, Thrombi-Pad, Thrombogen
Hepflush-10 , Hep-Lock, Hep-Lock U/P, Monoject Prefill Advanced Heparin Lock Flush, SASH Normal Saline and Heparin
Coumadin, Jantoven
Xarelto, Xarelto Granules, Xarelto Starter Pack
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