Fragile X (FMR1) Carrier Screening Test: Booking, Price, and Results
About Fragile X (FMR1) Carrier Screening Test: Booking, Price, and Results
| Field | Value |
|---|---|
| Also Known As | FMR1 Gene Test, Fragile X DNA Test, FMR1 CGG Repeat Analysis, Fragile X Mutation Analysis, FRAXA Test, Martin-Bell Syndrome Test |
| Sample Type | Peripheral blood (EDTA/lavender-top tube) |
| Fasting Required | No fasting required |
| Report Time | 35 days |
| Recommended For | Women planning pregnancy, individuals with a family history of fragile X or unexplained intellectual disability, and women with premature ovarian insufficiency |
| Price | Starting at ₹12,000 |
What is a Fragile X (FMR1) Carrier Screening Test?
The Fragile X (FMR1) carrier screening test analyses the FMR1 gene on the X chromosome to determine whether a person carries a genetic change that could be passed to their children. It counts the number of CGG trinucleotide repeats (a specific repeating DNA sequence) in the gene. This test is also known as the FMR1 gene test or Fragile X DNA test, and uses a small sample of peripheral blood collected in a lavender-top EDTA tube.
What Does a Fragile X (FMR1) Carrier Screening Test Measure?
The FMR1 test examines two key aspects of the FMR1 gene to determine carrier status. Here is what each component reveals:
| Component | What it Tells You |
|---|---|
| CGG Repeat Number | Counts the number of times a specific DNA segment repeats in the FMR1 gene; a higher count indicates a greater risk |
| Methylation Status | For large expansions, check whether the gene has been chemically switched off (relevant for premutation and full mutation cases) |
| Carrier Status | Identifies whether the individual carries a premutation that could expand into a full mutation in future generations |
Why is a Fragile X (FMR1) Carrier Screening Test Done?
A doctor may recommend the Fragile X (FMR1) carrier screening test for several reasons, including family history, reproductive planning, or unexplained symptoms in a child or adult.
Common Symptoms That May Require This Test
The following symptoms in a patient or their family members may prompt a referral for this test:
- Unexplained intellectual disability or developmental delay
- Speech and language delay in a child
- Features of autism spectrum disorder or learning difficulties of unknown cause
- Infertility or elevated FSH levels in a woman
- Premature ovarian insufficiency or irregular menstruation
- Tremor or balance problems (ataxia) in an older adult with a family history of fragile X
Conditions This Test Can Help Detect
This test can help identify or inform risk for the following conditions:
- Fragile X syndrome (FXS), the most common inherited cause of intellectual disability
- Fragile X-associated tremor/ataxia syndrome (FXTAS), a neurological condition seen in some older carriers
- Fragile X-associated primary ovarian insufficiency (FXPOI), which can cause early menopause and fertility difficulties
- Carrier status for reproductive planning purposes
Fragile X (FMR1) Carrier Screening Test During Pregnancy
The Fragile X (FMR1) carrier screening test is recommended for women with a family history of fragile X-related conditions or unexplained intellectual disability who are planning to conceive or are already pregnant. If a woman is found to be a carrier, further prenatal testing (by chorionic villus sampling or amniocentesis) can determine whether the foetus is affected. Identifying carrier status early allows couples to consider their full range of reproductive options.
How to Prepare and What to Expect
No special preparation is needed before the FMR1 test procedure. The following guidance will help your visit go smoothly.
Do You Need to Fast?
No fasting is required before this test. You may eat and drink normally before your appointment. There are no dietary restrictions of any kind.
Practical Tips Before Your Test
Keep the following points in mind before attending your sample collection appointment:
- Bring a detailed clinical history, including your symptoms, previous test results, and family history, as this is required for the test
- Inform your doctor about any medications or supplements you are currently taking
- Genetic counselling before the test is advisable, particularly if you are planning a pregnancy
- Bring any previous genetic test reports if available
- Wear clothing with easy access to your arm for the blood draw
Step-by-Step Procedure
- A trained phlebotomist (blood collection specialist) confirms your identity and reviews your clinical history documentation.
- The skin over a vein in your arm is cleaned with an antiseptic solution.
- A small sample of blood (approximately 2 ml) is drawn using a sterile needle into a lavender-top EDTA tube.
- The needle is removed, and a small cotton swab or bandage is placed on the site.
- The labelled blood sample is stored at a refrigerated temperature of 2 to 8 degrees Celsius.
- The sample is dispatched to the laboratory, where analysis is carried out using Sanger sequencing. Results are typically available within 35 days.
Factors That Can Affect Accuracy
Several factors can influence the reliability of your test result:
- A previous bone marrow transplant from another person (allogeneic donor) can interfere with testing
- Collecting blood in the wrong tube type or failing to maintain proper temperature during transport may affect DNA quality
- A small number of individuals with a clinical diagnosis of fragile X syndrome carry a different type of FMR1 variant (not a CGG expansion), which this test may not detect
- An incomplete or absent clinical history can limit the accurate interpretation of results
Understanding Your Fragile X (FMR1) Carrier Screening Test Results
Results from the Fragile X (FMR1) carrier screening test are reported as a CGG repeat number, which falls into one of the categories below. Always review your results with a qualified doctor or genetic counsellor.
| Result Category | CGG Repeat Range | Clinical Significance |
|---|---|---|
| Normal | Fewer than 10 to about 40 repeats | No identified risk of fragile X syndrome |
| Intermediate (Grey Zone) | 41 to 54 repeats | Slightly unstable; may expand over several generations |
| Premutation (Carrier) | 55 to 200 repeats | Carrier status; risk of passing a full mutation to offspring; personal risk of FXTAS or FXPOI |
| Full Mutation | More than 200 repeats | Fragile X syndrome is likely; the gene is typically silenced |
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 circumstances can affect how results are reported or interpreted:
- If you have had a bone marrow transplant from another donor, the result may not accurately reflect your own genetic status. Inform your doctor and the lab before testing.
- Methylation status is not assessed on chorionic villus samples taken during pregnancy, which may limit the information available from prenatal specimens.
How to Maintain Healthy Levels
Genetic carrier status cannot be changed through diet or lifestyle. The following steps, however, support informed decision-making:
- If you are identified as a carrier, seek genetic counselling before or during pregnancy to understand your options
- Early intervention and support programmes for children diagnosed with fragile X syndrome can meaningfully improve developmental outcomes
- Stay in regular contact with a specialist who can guide you on reproductive planning and family health monitoring
Lupin Diagnostics Fragile X (FMR1) Carrier Screening Test Price and Home Collection
The FMR1 test cost at Lupin Diagnostics starts at ₹12,000, and home sample collection is available across cities. The following table provides a city-wise price guide:
| City | Approximate Price (₹) |
|---|---|
| BHOPAL | 12000 |
| CHENNAI | 12000 |
| HYDERABAD | 12000 |
| KOLKATA | 12000 |
| NAVI MUMBAI | 12000 |
| PUNE | 12000 |
Disclaimer: Prices are indicative and may vary by location. Please confirm the current price at the time of booking.
How to Book
Follow these steps to book your FMR1 test online with Lupin Diagnostics:
- Select the Fragile X (FMR1) Carrier Screening 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
FMR1 test home collection is available across cities through Lupin Diagnostics, with sample pick-up carried out by trained, certified phlebotomists. All samples are processed in NABL-accredited laboratories, ensuring accurate and reliable results. Your digital report is shared directly via email or WhatsApp once ready.
Frequently Asked Questions
The Fragile X (FMR1) carrier screening test analyses the FMR1 gene to count the number of CGG repeats in a specific region of the gene. It tells you whether you carry a genetic change that could be passed to your children and cause Fragile X syndrome. The test uses a simple blood sample and requires no special preparation.
This test is recommended for women planning a pregnancy who have a family history of fragile X syndrome or unexplained intellectual disability. It is also relevant for women experiencing premature ovarian insufficiency, individuals with features of autism or developmental delay of unknown cause, and anyone with a known carrier in the family.
The FMR1 test is highly accurate, with results reported to be correct more than 99% of the time under normal conditions. However, factors such as a prior bone marrow transplant from another donor or poor sample quality can affect the outcome. Sanger sequencing, the method used at Lupin Diagnostics, is a well-established technique for CGG repeat analysis.
An intermediate result (41 to 54 CGG repeats) means your child is not at increased risk for fragile X syndrome right now. The repeat is considered slightly unstable and may potentially expand over multiple generations. A genetic counsellor can explain what this means for your family planning in more detail.
Yes. Men can carry a premutation in the FMR1 gene. A male carrier will pass the altered gene to all of his daughters but none of his sons. Male carriers generally do not develop fragile X syndrome themselves but may be at risk of developing FXTAS (a tremor and balance disorder) in later life.
This test needs to be done only once. The CGG repeat number in the FMR1 gene remains constant throughout a person's lifetime, so a single result is sufficient for lifetime carrier status determination.
Yes. Carrier screening can be performed during pregnancy. If the test identifies a woman as a carrier, her doctor may recommend further prenatal diagnostic testing, such as chorionic villus sampling or amniocentesis, to assess whether the foetus is affected.
Fragile X (FMR1) Carrier Screening Test: Booking, Price, and Results
