| Gene | RS ID | Effect Allele | Your Genotype | Notes About Effect Allele |
|---|---|---|---|---|
| F5 | rs6025 | T | -- | Factor V Leiden; Increase risk of blood clots (important) |
Understanding your data:
Your genotype is highlighted in yellow if you have one copy of the factor V Leiden allele. Your genotype is highlighted in orange if you have two copies of factor V Leiden.
One copy of the factor V Leiden allele (CT genotype) increases the risk of deep vein thrombosis by approximately 4-fold.
Two copies of the variant (TT genotype) increase the risk of deep vein thrombosis by approximately 11-fold.[ref][ref][ref][ref]
Background science:
Factor V Leiden is a genetic variant that affects blood clotting. Blood vessels are composed of tightly joined endothelial cells, and when a blood vessel is damaged, clotting is essential to prevent excessive bleeding. The clotting process involves platelets clumping together to form a clot at the site of the damage. Factors such as collagen and fibrinogen play important roles in strengthening the clot. Within the clotting cascade, various factors, including Factor V, are crucial for the activation and regulation of clotting. Factor V, encoded by the F5 gene, is a coagulation protein produced primarily in the liver. It is activated by thrombin and can bind to activated platelets. Mutations in the F5 gene can result in deficiencies in Factor V, leading to mild forms of hemophilia or impaired clotting. However, the Factor V Leiden variant causes the opposite effect, resulting in increased clotting activity due to the resistance to the shutdown signal from activated protein C.[ref]
Clinical Implications:
Factor V Leiden has been extensively studied and has been associated with an increased risk of deep vein thrombosis (DVT) and pulmonary embolism (PE). Meta-analyses combining data from multiple studies have estimated that individuals carrying one copy of the Factor V Leiden variant have a four-fold increased relative risk of thrombosis, while those with two copies have an eleven-fold increased risk.
It is important to note that not everyone carrying the Factor V Leiden variant will experience DVT or PE, but they are statistically more likely to be at a higher risk. The estimated annual incidence of DVT is 1 to 2 per 1000 adults, and for individuals homozygous for the variant, the 11-fold increased risk suggests a 1 to 2% risk of DVT in a given year.[ref][ref][ref][ref]
Preventative Measures and Lifestyle Recommendations:
It is important for individuals with the Factor V Leiden variant to discuss their genetic status with a healthcare professional to determine if preventative measures are necessary.
Full article on Factor V Leiden with links to more peer-reviewed studies.
Disclaimer: This report is for informational and educational purposes only. It is not intended to treat, diagnose, or cure any condition. Errors are possible in DTC genetic testing.