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F2 gene
URL of this page: https://medlineplus.gov/genetics/gene/f2/

F2 gene

coagulation factor II, thrombin

Normal Function

The F2 gene provides instructions for making a protein called prothrombin (also known as coagulation factor II). Coagulation factors are a group of related proteins that are essential for normal blood clotting (hemostasis). After an injury, clots protect the body by sealing off damaged blood vessels and preventing further blood loss.

Prothrombin is made chiefly by cells in the liver. The protein circulates in the bloodstream in an inactive form until an injury damages blood vessels. In response to the injury, prothrombin is converted to its active form, thrombin. Thrombin then converts a protein called fibrinogen into fibrin, the primary protein that makes up blood clots.

Thrombin is also thought to be involved in cell growth and division (proliferation), tissue repair, and the formation of new blood vessels (angiogenesis).

Health Conditions Related to Genetic Changes

Prothrombin deficiency

Several variants (also called mutations) in the F2 gene have been found to cause prothrombin deficiency, a bleeding disorder that slows the clotting process. Most of these variants change one protein building block (amino acid) in prothrombin. Some variants drastically reduce the activity of prothrombin and can lead to severe bleeding episodes. Other variants allow for a moderate amount of prothrombin activity, which typically causes mild bleeding episodes. None of the variants that are known to cause prothrombin deficiency eliminate prothrombin function. Researchers believe that some prothrombin is necessary for life.

More About This Health Condition

Prothrombin thrombophilia

Variants in the F2 gene may also cause prothrombin thrombophilia, an inherited disorder that is associated with excessive blood clotting. Most cases of this condition are caused by a variant that changes one DNA building block (nucleotide) in the F2 gene. Specifically, the nucleotide guanine is replaced with the nucleotide adenine at position 20210 (written as G20210A or 20210G>A). This variant, which occurs in a region of the gene called the 3' untranslated region, causes cells to produce too much prothrombin. More prothrombin leads to more thrombin, which promotes the formation of blood clots in the absence of injury. When these clots block blood flow, it can cause serious health complications.

More About This Health Condition

Other Names for This Gene

  • coagulation factor II
  • coagulation factor II (thrombin)
  • PT
  • RPRGL2
  • THPH1

Additional Information & Resources

Tests Listed in the Genetic Testing Registry

Scientific Articles on PubMed

Catalog of Genes and Diseases from OMIM

Gene and Variant Databases

References

  • Akhavan S, Mannucci PM, Lak M, Mancuso G, Mazzucconi MG, Rocino A, Jenkins PV, Perkins SJ. Identification and three-dimensional structural analysis of nine novel mutations in patients with prothrombin deficiency. Thromb Haemost. 2000 Dec;84(6):989-97. Citation on PubMed
  • Danckwardt S, Hartmann K, Gehring NH, Hentze MW, Kulozik AE. 3' end processing of the prothrombin mRNA in thrombophilia. Acta Haematol. 2006;115(3-4):192-7. doi: 10.1159/000090934. Citation on PubMed
  • Jayandharan G, Viswabandya A, Baidya S, Nair SC, Shaji RV, Chandy M, Srivastava A. Molecular genetics of hereditary prothrombin deficiency in Indian patients: identification of a novel Ala362 --> Thr (Prothrombin Vellore 1) mutation. J Thromb Haemost. 2005 Jul;3(7):1446-53. doi: 10.1111/j.1538-7836.2005.01402.x. Citation on PubMed
  • Kujovich JL. Prothrombin Thrombophilia. 2006 Jul 25 [updated 2021 Feb 4]. In: Adam MP, Feldman J, Mirzaa GM, Pagon RA, Wallace SE, Amemiya A, editors. GeneReviews(R) [Internet]. Seattle (WA): University of Washington, Seattle; 1993-2025. Available from http://www.ncbi.nlm.nih.gov/books/NBK1148/ Citation on PubMed
  • McGlennen RC, Key NS. Clinical and laboratory management of the prothrombin G20210A mutation. Arch Pathol Lab Med. 2002 Nov;126(11):1319-25. doi: 10.5858/2002-126-1319-CALMOT. Citation on PubMed
  • Spector EB, Grody WW, Matteson CJ, Palomaki GE, Bellissimo DB, Wolff DJ, Bradley LA, Prior TW, Feldman G, Popovich BW, Watson MS, Richards CS. Technical standards and guidelines: venous thromboembolism (Factor V Leiden and prothrombin 20210G >A testing): a disease-specific supplement to the standards and guidelines for clinical genetics laboratories. Genet Med. 2005 Jul-Aug;7(6):444-53. doi: 10.1097/01.gim.0000172641.57755.3a. Citation on PubMed
  • Sun WY, Witte DP, Degen JL, Colbert MC, Burkart MC, Holmback K, Xiao Q, Bugge TH, Degen SJ. Prothrombin deficiency results in embryonic and neonatal lethality in mice. Proc Natl Acad Sci U S A. 1998 Jun 23;95(13):7597-602. doi: 10.1073/pnas.95.13.7597. Citation on PubMed
  • Varga EA, Moll S. Cardiology patient pages. Prothrombin 20210 mutation (factor II mutation). Circulation. 2004 Jul 20;110(3):e15-8. doi: 10.1161/01.CIR.0000135582.53444.87. No abstract available. Citation on PubMed

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