Prothrombin G20210A (Factor II Mutation) Resources

A Genetic Clotting Condition or Thrombophilia

Prothrombin 20210 Mutation, also called Factor II Mutation is a genetic condition that causes an increase in the likelihood of your blood forming dangerous blood clots.

All individuals make the prothrombin (also called factor two) protein that helps blood clot. However, there are certain individuals who have a DNA mutation in the gene used to make prothrombin (also called prothrombin G20210A or the factor II (two) mutation). They are said to have an inherited thrombophilia (clotting disorder) called prothrombin G20210A. When this occurs, they make too much of the prothrombin protein.

Prothrombin G20210A and the tendency to develop blood clots

  • Normally, the prothrombin protein is produced to help the blood clot, and is produced in greater amounts after a blood vessel is damaged.
  • People who have a mutation in the prothrombin gene produce more prothrombin protein than is normal. Since there is more of the prothrombin protein in the blood, this increases the tendency to form clots.

Testing for prothrombin G20210A

Prothrombin testing is done by taking a blood sample, and using a genetic test to look at the prothrombin gene.

  • The DNA is isolated from blood cells and the prothrombin gene is examined to see if there is a mutation in the DNA code. If a gene change is found (the 20210st letter is changed from a G to an A), then the person has a prothrombin (or factor II) mutation.

Prevalence of prothrombin G20210A

A change in the prothrombin gene is present in 2-4% (or 1 in 50 to 1 in 25) of Caucasians, and is more common in individuals of European ancestry. In the United States, approximately 0.4% (about 1 in 250) of African Americans also have the mutation. Prothrombin G20210A mutation is rare in other groups.

Signs and Symptoms of Blood Clots – What You Need to Know

If you have Prothrombin 20210 Mutation (Factor II), you need to be aware of the symptoms of DVTs (Deep Vein Thrombosis or leg or arm clot) so you can seek medical attention.

If you have a Deep Vein Thrombosis or DVT you will notice:

  • Pain or tenderness in your arm or leg – often described as a cramp or Charley horse – with one or more of the following:
    1. Swelling
    2. Red or purple skin color
    3. Warm to the touch

    If a piece of a DVT breaks off and travels to the lung, it can cause a lung clot. We call this a pulmonary embolism or PE. A PE can be a life threatening medical emergency. You need to seek immediate medical attention if you have symptoms of a PE.

    If you have a Pulmonary Embolism or PE (lung clot), you may experience:

      • Hard to breath or shortness of breath
      • Chest pain – especially when trying to breathe
      • Rapid or racing heart beat
      • Fainting or passing out

    Resources for More Information

    You can find more about Prothrombin G20210A (Factor II Mutation) at the links below:

    You can read more about Prothrombin G20210A (Factor II Mutation) at the links below:

          1. Prothrombin 20210 Mutation (Factor II Mutation): (2004) A patient oriented journal articles that discusses the basics of blood clotting, the prothrombin/prothrombin genetic mutation, how you get the prothrombin mutation, how it is diagnosed and treated, implications for women, testing family members, and minimizing risks. From the American Heart Association’s Circulation Journal.
          2. Prothrombin-Related Thrombophilia: (2011) Discusses characteristics of Protrombin related thrombophilias, how it is diagnosed, treated, and managed, risks (including pregnancy) and prevention of complications, extensive genetics information with genotype/phenotype correlations, genetic testing, genetic counseling and other genetic blood clotting disorders that can occur with Prothrombin G20210A (Factor II Mutation). GeneReviews™ [Internet] from the National Center for Biological Information of the National Library of Medicine of the National Institutes of Health
          3. Factor II  (2013) A more technical discussion with an in-depth discussion of the genetics of Factor II, its signs & Symptoms, how it is acquired and inherited, how it is diagnosed and treated, and lab tests and medications used with it. From Medscape.

    You can read about people who have had Prothrombin G20210A (Factor II Mutation) and Blood Clots in their own voices:

    Patient Stories of Prothrombin G20210A (Factor II Mutation)

  • In Memory of Ashleigh Littlefield: Her Blood Clot Story
  • Victoria Fisher’s Blood Clot Story
  • Melanie Friedman’s Blood Clot Story
  • Samara McAuliffe’s Blood Clot Story
  • Jessica Phillips DVT/PE Blood Clot Survival Story
  • Helen Smith’s Blood Clot Story

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