From the Research
Factor V Leiden syndrome is inherited in an autosomal dominant pattern, meaning a person only needs to inherit one copy of the mutated gene from either parent to develop the condition. This condition results from a specific mutation in the F5 gene, which produces Factor V, a protein involved in blood clotting, as discussed in 1. The mutation makes Factor V resistant to inactivation by protein C, leading to increased clotting tendency. People who inherit two copies of the mutation (one from each parent) have a higher risk of developing blood clots than those with just one copy.
Key Points
- Each child of a parent with Factor V Leiden has a 50% chance of inheriting the mutation.
- Factor V Leiden is particularly common in individuals of European descent, affecting about 5% of Caucasians, but is less common in other ethnic groups, as noted in 2.
- The presence of this mutation increases the risk of developing deep vein thrombosis and other clotting disorders, though many people with the mutation never develop clots, as discussed in 3.
Inheritance Pattern
The autosomal dominant pattern of inheritance means that a single copy of the mutated gene is enough to increase the risk of developing blood clots. This is in contrast to autosomal recessive conditions, where an individual would need to inherit two copies of the mutated gene (one from each parent) to develop the condition.
Clinical Implications
Understanding the inheritance pattern of Factor V Leiden is crucial for assessing the risk of developing blood clots in individuals and their family members. As noted in 4, testing for Factor V Leiden can help identify individuals at increased risk, allowing for early intervention and prevention of thrombotic events. However, the decision to test for Factor V Leiden should be made on an individual basis, taking into account the person's medical history, family history, and other risk factors, as discussed in 5.