Factor V Leiden Test
Private Factor V Leiden genetic test in London for £198, detecting one inherited thrombophilia variant with results expected in around 2 weeks.
Turnaround time
2 weeks
Biomarkers count
1
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Overview of the Factor V Leiden Test
The Factor V Leiden Test is a specialist genetic blood test used to detect the common Factor V Leiden mutation within the F5 gene.
The test contains 1 biomarker: Factor V Leiden - common mutation.
Factor V is a protein involved in the blood-coagulation cascade.
Once a clot has begun forming, activated Protein C normally helps limit coagulation by inactivating activated Factor V.
The Factor V Leiden genetic variant changes Factor V so that it becomes resistant to inactivation by activated Protein C.
This is known as activated Protein C resistance.
The result is a tendency for the coagulation system to remain active for longer than usual, increasing susceptibility to venous blood clots.
Factor V Leiden is one of the most common inherited thrombophilias in people of European ancestry.
The variant is primarily associated with deep vein thrombosis and pulmonary embolism.
Having Factor V Leiden does not mean that a blood clot is inevitable.
Many people with one copy of the mutation never develop thrombosis.
Risk becomes more important when the mutation combines with acquired factors such as surgery, prolonged immobilisation, pregnancy, oestrogen-containing medication, obesity, increasing age or another thrombophilia.
People can inherit either one copy of the mutation, described as heterozygous, or two copies, described as homozygous.
Homozygous Factor V Leiden is considerably less common and is associated with a greater thrombotic risk.
Because this is a DNA test, the result does not change throughout life and usually only needs to be performed once.
What Does the Factor V Leiden Test Check ?
This test measures 1 biomarker.
Factor V Leiden - common mutation
Detects the common inherited F5 gene variant responsible for activated Protein C resistance and an increased susceptibility to venous thrombosis.
Who May Benefit From the Factor V Leiden Test?
Testing may be useful where personal or family history suggests an inherited tendency towards venous thrombosis.
People with an unexplained DVT - Factor V Leiden is an established inherited risk factor for venous thrombosis.
People with an unexplained pulmonary embolism - Genetic thrombophilia may contribute when a PE occurs without a major temporary trigger.
People who develop venous thrombosis at a relatively young age - Earlier events can increase suspicion of inherited risk.
People with recurrent blood clots - Specialist thrombophilia assessment may occasionally be appropriate.
People with multiple first-degree relatives affected by venous thrombosis - A strong family history can suggest inherited susceptibility.
People with a relative known to carry Factor V Leiden - Targeted genetic testing can establish whether the variant was inherited.
People undergoing selected pregnancy or reproductive thrombophilia investigations - Genetic testing may occasionally be requested according to specialist guidance.
People with another inherited thrombophilia - Combined risk factors can increase overall thrombosis susceptibility.
People specifically advised to obtain Factor V Leiden testing - Testing is most useful where the result could influence counselling or management.
How to Prepare
Do not discontinue anticoagulant medication for the purpose of this genetic test.
DNA does not change according to medication or current clotting status.
Symptoms and Reasons to Consider the Factor V Leiden Test
Factor V Leiden itself causes no day-to-day symptoms. Symptoms occur only if a clinically important clot develops.
Pain and swelling affecting one leg - These are common symptoms of deep vein thrombosis.
Redness or warmth in one leg - Local inflammatory changes can occur around a DVT.
Sudden unexplained breathlessness - Pulmonary embolism can cause acute respiratory symptoms.
Chest pain that worsens when breathing - This can occur with a pulmonary embolism.
Coughing blood - Haemoptysis can occur with significant pulmonary embolism.
A previous unexplained DVT or PE - Genetic testing can contribute to determining whether inherited risk exists.
Blood clots affecting several close relatives - Familial clustering can increase the relevance of testing.
A clot occurring during pregnancy, oestrogen exposure or another recognised risk period - An inherited factor can sometimes contribute alongside the acquired trigger.
Factor V Leiden itself does not require emergency treatment.
However, new symptoms of DVT, pulmonary embolism or another acute clot require urgent medical assessment rather than waiting for genetic testing.
How to Book Your Factor V Leiden Test in London
Booking your Factor V Leiden Test with London Blood Tests is straightforward.
Choose the Factor V Leiden Test
Select the individual Factor V Leiden genetic test.
Select your sample collection option
Choose an in-clinic blood draw or professional home or hotel phlebotomy.
Attend your appointment
A trained professional collects the required blood specimen.
Laboratory analysis
Your DNA is analysed for the common Factor V Leiden mutation.
Receive your results securely
Your authorised genetic report is delivered securely for discussion with a GP or haematologist where appropriate.
When Will I Receive My Results?
The current London Blood Tests customer-facing turnaround for the Factor V Leiden Test is approximately 2 weeks after your sample reaches the laboratory.
This is a specialist molecular genetic investigation rather than a routine coagulation assay.
The specimen undergoes DNA analysis, quality assurance and laboratory authorisation before the report can be released.
Because the result is genetic and permanent, there is no clinical advantage to repeatedly testing once a valid genotype has been established.
Understanding Your Results
A negative result means the common Factor V Leiden mutation was not detected.
This reduces the likelihood that Factor V Leiden contributes to your clotting risk but does not exclude other inherited or acquired thrombophilias.
A heterozygous positive result means one copy of the F5 gene carries the Factor V Leiden variant.
This increases relative venous thrombosis risk compared with someone without the mutation.
A homozygous positive result means both gene copies carry the variant.
This is much less common and is associated with a greater risk.
The absolute chance of developing a clot depends strongly on other risk factors.
Surgery, immobility, pregnancy, oestrogen treatment, obesity and additional thrombophilias can combine with the genetic tendency.
A positive result does not automatically mean that lifelong anticoagulation is required.
Clinical management is based on personal clotting history and overall risk.
Why Book With London Blood Tests?
Private Factor V Leiden testing in London - Access targeted inherited thrombophilia analysis privately.
Permanent genetic result - The mutation status does not change over time.
Relevant to unexplained venous thrombosis - Factor V Leiden is an established inherited clot-risk factor.
Useful when the mutation runs in a family - Targeted testing can establish whether the variant was inherited.
Not affected by blood-thinning medication - Anticoagulants do not change the DNA result.
Specialist genetic laboratory analysis - Your sample undergoes validated molecular testing.
Secure reporting - Receive your authorised genetic result securely.
Clear pricing - The Factor V Leiden Test costs £198.
Private Factor V Leiden Test in London
London Blood Tests provides private Factor V Leiden genetic testing in London for people requiring assessment of inherited venous thrombosis risk.
The test costs £198 and measures one biomarker: Factor V Leiden - common mutation.
Current customer-facing results are expected approximately 2 weeks after laboratory receipt.
A positive result identifies an inherited risk factor rather than a certainty that thrombosis will occur.