Factor V (Leiden) Mutation Analysis

The Factor V (Leiden) Mutation Analysis test contains 1 test with 3 biomarkers.

Brief Description: The Factor V (Leiden) Mutation Analysis test is a specialized genetic test used to identify the presence of a specific mutation in the factor V gene. This mutation is associated with an increased risk of developing abnormal blood clots in veins, a condition known as venous thromboembolism.

Collection Method: Blood Draw

Specimen Type: Serum

Test Preparation: No preparation required

When and Why a Factor V (Leiden) Mutation Analysis Test May Be Ordered

A physician might order the Factor V (Leiden) Mutation Analysis test:

• Family History: In individuals who have a family history of unexplained blood clots or venous thromboembolism.

• Unexplained Blood Clots: Especially in younger individuals or those without obvious risk factors for clotting.

• Recurrent Miscarriages: Some women with the mutation may experience recurrent miscarriages.

• Before Prescribing Certain Medications: Such as oral contraceptives or hormone replacement therapy, especially if there's a known family history of the mutation or thrombotic events.

What the Factor V (Leiden) Mutation Analysis Test Checks For

This test specifically checks for a mutation in the factor V gene. The mutation causes a specific change in the factor V protein, making it resistant to a molecule called activated protein C (APC). APC usually helps prevent blood from clotting too easily, so this resistance results in a higher risk of clot formation.

Other Lab Tests Ordered Alongside the Factor V (Leiden) Mutation Analysis Test

When a Factor V Leiden test is ordered, it's often part of a broader evaluation of hypercoagulability (increased tendency to form blood clots). Here are some tests commonly ordered alongside it:

1. Prothrombin G20210A Mutation Analysis:

   • Purpose: To detect a mutation in the prothrombin gene, another common genetic cause of increased clotting risk.
   • Why Is It Ordered: Like Factor V Leiden, the prothrombin G20210A mutation increases the risk of thrombosis, and testing for both can help assess the overall risk more accurately.

2. Activated Protein C Resistance (APCR) Test:

   • Purpose: To assess the response of the blood to activated protein C, which is an anticoagulant.
   • Why Is It Ordered: The Factor V Leiden mutation causes resistance to activated protein C, leading to increased clotting risk. This test can indirectly detect the presence of Factor V Leiden mutation.

3. Antiphospholipid Antibodies (such as anticardiolipin antibodies and beta-2 glycoprotein I antibodies):

   • Purpose: To detect antibodies associated with antiphospholipid syndrome, another cause of increased clotting risk.
   • Why Is It Ordered: To evaluate for other causes of thrombophilia, particularly in patients with a history of blood clots or recurrent miscarriages.

4. Complete Blood Count (CBC):

   • Purpose: To evaluate overall blood health.
   • Why Is It Ordered: To identify any underlying conditions such as polycythemia (increased red blood cells) or thrombocytosis (increased platelets), which can affect clotting.

5. D-Dimer Test:

   • Purpose: To detect the presence of fibrin degradation products, which are present after a blood clot is formed and then broken down.
   • Why Is It Ordered: To assess for recent or ongoing clotting activity, particularly in patients with suspected deep vein thrombosis (DVT) or pulmonary embolism (PE).

6. PT/INR and aPTT:

   • Purpose: To assess the blood's ability to clot properly.
   • Why Is It Ordered: To evaluate the overall coagulation status, particularly if the patient is on anticoagulant therapy or has a history of bleeding or clotting disorders.

7. Homocysteine Level:

   • Purpose: To measure the level of homocysteine in the blood.
   • Why Is It Ordered: Elevated homocysteine levels can increase the risk of thrombosis and are associated with certain vitamin deficiencies and metabolic conditions.

8. Lipid Profile:

   • Purpose: To measure levels of cholesterol and triglycerides.
   • Why Is It Ordered: While not directly related to clotting, a lipid profile can be part of a comprehensive cardiovascular risk assessment, especially in patients with a history of thrombosis.

These tests, when ordered alongside a Factor V Leiden Mutation Analysis, provide a comprehensive evaluation of an individual’s risk for thrombosis. They help in diagnosing inherited and acquired clotting disorders, assessing the severity of the risk, and guiding treatment and management decisions. The specific combination of tests will depend on the individual’s medical history, family history, and any symptoms or conditions they have.

Conditions or Diseases that Require a Factor V (Leiden) Mutation Analysis Test

• Venous Thromboembolism (VTE): This includes deep vein thrombosis (DVT), where clots form deep in the legs, and pulmonary embolism (PE), where a clot travels to the lungs.

• Recurrent Miscarriages: In some cases, abnormal clotting may be a reason for recurrent miscarriages.

Usage of Factor V (Leiden) Mutation Analysis Test Results by Health Care Providers

Healthcare providers use the results of the Factor V (Leiden) Mutation Analysis test to:

• Risk Assessment: Determine the risk of developing blood clots in those individuals who have a family history of clotting disorders or who have experienced unexplained blood clots.

• Guide Treatment: If the mutation is found, individuals may be advised to avoid certain medications that can further increase the risk of clotting. Additionally, they might be prescribed anticoagulant medications if deemed at high risk.

• Counseling: Provide genetic counseling regarding the implications of the mutation and the potential risks to offspring.

In conclusion, the Factor V (Leiden) Mutation Analysis test is an essential tool for identifying individuals at increased risk for venous thromboembolism. Understanding one's genetic predisposition can guide preventive measures and treatments to manage and reduce the risks associated with this mutation.

Most Common Questions About the Factor V (Leiden) Mutation Analysis test:

Purpose and Indications of the Factor V (Leiden) Mutation Analysis Test

What is the purpose of the Factor V (Leiden) Mutation Analysis test?

The Factor V (Leiden) Mutation Analysis test is designed to identify the presence of a specific mutation in the F5 gene, which is associated with an increased risk of developing abnormal blood clots in veins, a condition known as venous thromboembolism.

Why might someone be recommended to take the Factor V (Leiden) Mutation Analysis test?

Individuals might be recommended to take this test if they have a personal or family history of multiple unexplained blood clots or if they've experienced abnormal blood clotting at a young age. It can help determine if they carry the mutation that puts them at an increased risk.

Interpreting the Results

What do the results of the Factor V (Leiden) Mutation Analysis test indicate?

If the test is positive, it means that the individual has one or two copies of the Factor V Leiden mutation, putting them at a higher risk for blood clots. A negative result means that the individual does not have the mutation and their risk of blood clotting is based on other factors.

What's the difference between being homozygous and heterozygous for the Factor V Leiden mutation based on the test results?

Being homozygous means that an individual has two copies (one from each parent) of the Factor V Leiden mutation, which significantly increases their risk of blood clotting. Being heterozygous means the person has only one copy of the mutation and their risk is elevated, but not as much as if they were homozygous.

Implications and Management

If an individual tests positive for the Factor V (Leiden) Mutation Analysis test, how might their medical management change?

If someone tests positive, especially if they have a history of blood clots or other risk factors, their healthcare provider might recommend preventive measures. These could include avoiding long periods of immobility, using compression stockings, or taking anticoagulant medications during high-risk situations like surgery or long flights.

Is it advisable for family members to get tested if one member is positive for the Factor V (Leiden) Mutation Analysis test?

Yes, since the Factor V Leiden mutation is inherited, if one family member tests positive, it may be advisable for other family members, especially first-degree relatives like siblings or children, to consider testing. This can help them understand their own risk and take preventive measures if necessary.

Test Mechanisms and Specifics

Are there conditions or other genetic factors that might coexist and increase the risk of blood clotting in someone positive for the Factor V (Leiden) Mutation Analysis test?

Yes, there are other genetic mutations and conditions, like the prothrombin G20210A mutation, that can increase the risk of clotting. If someone has both Factor V Leiden and another clotting risk factor, their overall risk is compounded and significantly higher than having just one risk factor alone.

How does the Factor V (Leiden) Mutation Analysis test differ from other tests that evaluate clotting risk?

The Factor V (Leiden) Mutation Analysis test specifically looks for a genetic mutation in the F5 gene. Other tests might assess the function of the clotting system, measure specific clotting factors, or look for other genetic mutations associated with clotting disorders. It's important to understand that while the Factor V Leiden test provides valuable information, a comprehensive evaluation of clotting risk might involve multiple tests.

Additional Information

Is the Factor V (Leiden) Mutation Analysis test used for any other purposes apart from assessing clotting risk?

Primarily, the test is used to assess clotting risk. However, it might also be considered in cases of recurrent miscarriage as women with the Factor V Leiden mutation may have a slightly increased risk of pregnancy loss, although the evidence is not conclusive.

What other factors, apart from the Factor V (Leiden) mutation, can contribute to an increased risk of blood clots?

Several factors can increase the risk of blood clots, including prolonged immobility, surgery, certain medications (like hormone replacement therapy or oral contraceptives), pregnancy, obesity, smoking, cancer, and other inherited or acquired clotting disorders. It's essential to consider the full clinical picture when assessing an individual's risk.

We advise having your results reviewed by a licensed medical healthcare professional for proper interpretation of your results.