Haemophilia A Common Mutation Screening (Factor VIII Intron 22 Inversion Analysis) Test
About Haemophilia A Common Mutation Screening (Factor VIII Intron 22 Inversion Analysis) Test
| Field | Value |
|---|---|
| Also Known As | F8 Intron 22 Inversion Test, Intron 22 Inversion Analysis, FVIII Intron 22 Inversion Screening, Haemophilia A Genetic Mutation Test |
| Sample Type | Peripheral blood (whole blood in EDTA tube) |
| Fasting Required | No fasting required |
| Report Time | 15 days |
| Recommended For | Males with severe haemophilia A; females at risk of being carriers due to family history; prenatal diagnosis in known carrier families |
| Price | Starting at ₹12,000 |
What is a Haemophilia A Common Mutation Screening (Factor VIII Intron 22 Inversion Analysis) Test?
The Haemophilia A common mutation screening (Factor VIII intron 22 inversion analysis) test is a specialised genetic test that detects a specific mutation in the F8 gene, which is responsible for producing clotting Factor VIII. The intron 22 inversion is the single most common mutation linked to severe haemophilia A, accounting for roughly 45% of all severe cases. A small blood sample collected in an EDTA tube is all that is needed to perform this test. It is also known as the F8 Intron 22 Inversion Test or Haemophilia A Genetic Mutation Test.
What Does a Haemophilia A Common Mutation Screening (Factor VIII Intron 22 Inversion Analysis) Test Measure?
This test looks for one specific genetic change inside the F8 gene. Here is what is analysed and why it matters:
| Parameter | What it Detects | Why it Matters |
|---|---|---|
| Intron 22 Inversion Status | Presence or absence of the inversion mutation in the F8 gene | Confirms or rules out this specific cause of severe haemophilia A; identifies carriers in females |
The intron 22 inversion occurs when a segment of genetic material inside the F8 gene flips and rearranges. This disrupts the gene's normal function and prevents the body from producing adequate amounts of Factor VIII, a protein essential for blood clotting.
Why is a Haemophilia A Common Mutation Screening (Factor VIII Intron 22 Inversion Analysis) Test Done?
Doctors order this test to confirm a genetic cause of bleeding disorders, identify carriers in families, and support family planning decisions.
Common Symptoms That May Require This Test
The following symptoms may prompt a doctor to recommend this test:
- Excessive or prolonged bleeding from minor cuts or injuries
- Easy bruising with no clear cause
- Frequent or unexplained nosebleeds
- Joint pain and swelling caused by internal bleeding
- Bleeding that does not stop after surgery, a dental procedure, or an injury
- Blood in urine or stools
- Heavy menstrual bleeding in women with a family history of haemophilia A
Conditions This Test Can Help Detect
The test helps identify or confirm the following conditions:
- Severe haemophilia A caused by the intron 22 inversion mutation in the F8 gene
- Carrier status in women who have a family history of severe haemophilia A
- The need for further genetic testing to determine if other F8 mutations may be responsible
Haemophilia A Common Mutation Screening (Factor VIII Intron 22 Inversion Analysis) Test During Pregnancy
This screening may be suggested for women without a known family history of haemophilia A during antenatal care. A positive result in a woman indicates that her male offspring may be at risk, enabling further prenatal diagnosis. Knowing a woman's F8 mutation status before or during pregnancy allows for timely and efficient prenatal evaluation. Preconception genetic counselling is recommended to help families understand their options.
How to Prepare and What to Expect
No special preparation is needed for this test. The steps below explain what the process involves.
Do You Need to Fast?
No. Fasting is not required before this test. You can eat and drink normally on the day of sample collection.
Practical Tips Before Your Test
A few simple steps will help the process go smoothly:
- Bring a detailed clinical history, including your symptoms, previous test results, and family history, as this is required for the test
- Carry any earlier haemophilia-related test reports for reference
- Inform your doctor or the phlebotomist about all medications you are currently taking, especially blood-thinning drugs
- Genetic counselling before and after testing is recommended to help you understand the results
Step-by-Step Procedure
Here is what to expect during sample collection:
- A trained phlebotomist cleans the skin on your inner arm with an antiseptic solution.
- A tourniquet (a soft elastic band) is applied to your upper arm to make the vein easier to locate.
- A small blood sample of 2 ml is drawn from the vein using a fine needle into an EDTA (lavender-top) tube.
- The needle is removed, and light pressure is applied to the site to stop any minor bleeding.
- The sample is labelled with your details and stored under refrigerated conditions (2 to 8 degrees Celsius) for safe transport to the laboratory.
- At the laboratory, the sample undergoes MLPA (Multiplex Ligation-dependent Probe Amplification) analysis to detect the presence or absence of the intron 22 inversion.
Factors That Can Affect Accuracy
The following factors may affect the reliability of the test result:
- An incomplete or inaccurate clinical history provided at the time of testing
- Poor sample handling or a break in cold-chain storage during transport
- Sample contamination during collection
- The presence of other F8 gene mutations not targeted by this specific assay
Understanding Your Haemophilia A Common Mutation Screening (Factor VIII Intron 22 Inversion Analysis) Test Results
Results from this test are reported as either detected or not detected. A doctor or genetic counsellor should always review the findings alongside your clinical history and family background.
| Result | Interpretation |
|---|---|
| Not Detected (Negative) | The intron 22 inversion mutation is absent; does not exclude other F8 mutations |
| Detected, Positive (Male) | Affected with severe haemophilia A due to this specific mutation |
| Detected, Positive (Female) | Carrier of the haemophilia A intron 22 inversion mutation |
Disclaimer: These ranges are general guidelines. Your doctor will interpret your results based on your age, health history, and other factors. Always consult a qualified healthcare professional for personalised medical advice.
Results During Special Conditions
Certain situations can make results more complex to interpret:
- Female carriers are usually symptom-free because their Factor VIII levels are approximately half of normal. In rare cases, a carrier may experience moderate to severe bleeding symptoms due to skewed inactivation of her unaffected X chromosome.
- Not all mothers of an affected child are confirmed carriers. Roughly 20% of mothers of isolated haemophilia A cases do not carry an identifiable F8 mutation in their germline. A small risk of recurrence may still exist due to the possibility of germline mosaicism (where only some cells carry the mutation).
How to Maintain Healthy Levels
Because this is a genetic test, results reflect your inherited DNA and cannot be changed. However, the following steps support better health management:
- If your result is positive, seek genetic counselling before making family planning decisions
- Maintain regular follow-up appointments with a haematologist (a blood specialist) if haemophilia A has been diagnosed
- Female carriers should inform their doctors, dentists, and surgeons of their carrier status to plan for potential bleeding risks during procedures or childbirth
Lupin Diagnostics Haemophilia A Common Mutation Screening (Factor VIII Intron 22 Inversion Analysis) Test Price and Home Collection
The Haemophilia A common mutation screening (Factor VIII intron 22 inversion analysis) test is available at Lupin Diagnostics, starting at ₹12,000, with home sample collection available across cities.
| City | Approximate Price (₹) |
|---|---|
| Mumbai | 12000 |
| Pune | 12000 |
| Bangalore | 12000 |
| Chennai | 12000 |
Disclaimer: Prices are indicative and may vary by location. Please confirm the current price at the time of booking.
How to Book
Booking the Haemophilia A common mutation screening (Factor VIII intron 22 inversion analysis) test online is simple:
- Select the test on the Lupin Diagnostics website.
- Choose your city and preferred time slot.
- Opt for home sample collection by a certified phlebotomist, or visit your nearest Lupin Diagnostics centre.
- Receive your report via email or WhatsApp within the stipulated turnaround time.
Home Collection
The Haemophilia A common mutation screening (Factor VIII intron 22 inversion analysis) test home collection service is available across major cities in India. All samples are processed in NABL-accredited laboratories by experienced professionals. Your digital report is delivered securely via email or WhatsApp once ready.
Frequently Asked Questions
The intron 22 inversion is a rearrangement of genetic material within the F8 gene that disrupts Factor VIII production. Together with the intron 1 inversion, it accounts for approximately 50% of severe haemophilia A cases. Detecting this mutation helps confirm a diagnosis and enables carrier identification within families.
This test is recommended for males with a clinical diagnosis of severe haemophilia A, women with a family history of severe haemophilia A who may be carriers, and pregnant women in known carrier families who wish to assess the risk to their unborn child.
Female carriers usually do not experience bleeding symptoms because they carry one working copy of the F8 gene. However, approximately 10% of female carriers have sufficiently low Factor VIII levels to be at risk of bleeding, particularly during surgery, dental work, or childbirth.
A negative result means the intron 22 inversion mutation was not found in your sample. This does not completely rule out haemophilia A, as other mutations in the F8 gene may be responsible. Your doctor may recommend additional testing, such as full F8 gene sequencing, if haemophilia A is still suspected.
When the intron 22 inversion has been identified in a family member, this test can be used for prenatal diagnosis to determine whether an unborn male child is affected. Genetic counselling is strongly recommended before undergoing prenatal testing to understand all available options.
The procedure involves a routine blood draw, which most people find mildly uncomfortable at most. A small blood sample of 2 ml is collected from a vein in your arm. The process takes only a few minutes and does not require any injections or special preparation.
No. This is a one-time genetic test. Your mutation status is determined by your DNA, which does not change over your lifetime. Once the intron 22 inversion result has been established, you do not need to repeat this specific test.
Haemophilia A Common Mutation Screening (Factor VIII Intron 22 Inversion Analysis) Test
