About our e-newsletters
- Free e-newsletters
- Mayo Clinic expertise
- We do not share your e-mail address
Housecall, our weekly general-interest e-newsletter, keeps you up to date on a wide variety of health topics with timely, reliable, practical information, recipes, blogs, questions and answers with Mayo Clinic experts and more. Our biweekly topic-specific e-newsletters also include blogs, questions and answers with Mayo Clinic experts, and other useful information that will help you manage your health.
Housecall Archives
Mayo Clinic Housecall
Stay up to date on the latest health information.
What you get
- Free weekly e-newsletter
- Mayo Clinic expertise
- Recipes, tools and other helpful information
- We do not share your e-mail address
Causes
By Mayo Clinic staffA blood clot (thrombus) normally forms to stop the bleeding when an artery or vein is damaged, such as when you experience a cut. Clots form as a result of chemical reactions between specialized blood cells (platelets) and proteins in your blood (clotting factors). Substances in the blood known as anti-clotting factors control excessive formation of blood clots.
Normally, factor V is a clotting protein. But, people with factor V Leiden have a genetic mutation that causes the factor V protein to respond more slowly to the anti-clotting factors.
In the normal clotting process, anti-clotting proteins combine to help break up factor V to keep it from being reused and forming clots when clotting isn't needed. However, the factor V Leiden mutation keeps the anti-clotting proteins from breaking down factor V, which keeps it in the blood longer and increases the chance of clotting.
If you have factor V Leiden, you either inherited one copy of the defective gene (heterozygous), which slightly increases your risk of developing blood clots, or you inherited two copies, one from each parent (homozygous), which significantly increases your risk of developing blood clots.
- Learning about factor v Leiden thrombophilia. National Human Genome Research Institute. http://www.genome.gov/pfv.cfm?pageID=15015167. Accessed May 21, 2010.
- Ornstein DL, et al. Factor V Leiden. Circulation. 2003;107:e94.
- Deep vein thrombosis. The Merck Manuals: The Merck Manual for Healthcare Professionals. http://www.merck.com/mmpe/print/sec07/ch081/ch081b.html. Accessed May 21, 2010.
- Pulmonary embolism. The Merck Manuals: The Merck Manual for Healthcare Professionals. http://www.merck.com/mmpe/print/sec05/ch050/ch050a.html. Accessed May 21, 2010.
- Laubach J, et al. Hematological changes of pregnancy. In: Hoffman R, et al. Hematology: Basic Principles and Practice. 5th ed. Philadelphia, Pa.: Churchill Livingstone Elsevier; 2008. http://www.mdconsult.com/book/player/book.do?method=display&type=aboutPage&decorator=header&eid=4-u1.0-B978-0-443-06715-0..X5001-8--TOP&isbn=978-0-443-06715-0&uniq=203749156. Accessed May 21, 2010.
- Konkle BA, et al. Hemostasis, thrombosis, fibrinolysis, and cardiovascular disease. In: Libby P, et al. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine. 8th ed. Philadelphia, Pa.: Saunders Elsevier; 2007. http://www.mdconsult.com/book/player/book.do?method=display&type=aboutPage&decorator=header&eid=4-u1.0-B978-1-4160-4106-1..X5001-8--TOP&isbn=978-1-4160-4106-1&uniq=203749156. Accessed May 21, 2010.
Find Mayo Clinic on