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Prothrombin (Factor II) 20210 Gene Mutation


Joel L. Moake

, MD, Baylor College of Medicine

Last full review/revision Jan 2021| Content last modified Jan 2021
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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). 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.

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 of either thrombin (dabigatran) or factor Xa (eg, rivaroxaban, apixaban) can be used in place of other anticoagulants for this disorder.

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Test your knowledge

Overview of Thrombotic Disorders
Thrombotic disorders can be caused by genetic defects, which increase the risk of venous thromboembolism, or acquired defects, which increase the risk of arterial and venous thrombosis. Of the acquired causes, which of the following is most likely to increase a patient’s risk of venous thrombosis?
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