Factor V
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Factor V is a protein in the blood that helps blood clot. It's also known as proaccelerin or labile factor.
Factor V is a cofactor glycoprotein that's required for both the coagulation and anticoagulation pathways. It's not enzymatically active, but it interacts with other clotting proteins to increase the production of thrombin. Thrombin is the enzyme that converts fibrinogen to a fibrin clot.
Factor V is synthesized in several cell types, but the liver is generally considered the primary site of biosynthesis.
Factor V deficiency can lead to a predisposition for hemorrhage. Some mutations can also predispose for thrombosis.
The risk of developing an abnormal blood clot increases with the presence of the factor V Leiden mutation. Having one copy of the mutation increases the risk to 3 to 8 in 1,000, and having two copies may raise the risk to as high as 80 in 1,000.
Some steps that might help prevent injury and avoid excessive bleeding include:
- Avoiding contact sports or other activities that could result in physical injury
- Using a soft toothbrush and waxed floss