RETT Syndrome (MECP2 Mutation Analysis) Test
About RETT Syndrome (MECP2 Mutation Analysis) Test
| Field | Value |
|---|---|
| Also Known As | MECP2 Gene Mutation Analysis, MECP2 Sequencing, Rett Syndrome Genetic Test, MECP2 Deletion/Duplication Analysis |
| Sample Type | Whole blood (EDTA tube) |
| Fasting Required | No fasting required |
| Report Time | 15 days |
| Recommended For | Primarily females (infants and children) showing signs of developmental regression; rarely ordered for males with severe encephalopathy or intellectual disability |
| Price | Starting at ₹7,000 |
What is a RETT Syndrome (MECP2 Mutation Analysis) Test?
The RETT Syndrome test is a specialised genetic test that examines the MECP2 gene for changes that may cause Rett syndrome and related neurological disorders. It analyses DNA extracted from a blood sample using a method called Sanger sequencing, which reads the gene one letter at a time. Doctors typically order this test for young girls who show signs of developmental regression. It is also known as MECP2 sequencing or MECP2 Gene Mutation Analysis.
What Does a RETT Syndrome (MECP2 Mutation Analysis) Test Measure?
This is a qualitative genetic test. Rather than producing numerical values, it identifies whether disease-causing changes are present in the MECP2 gene. The MECP2 gene sits on the X chromosome and carries instructions for making a protein that helps regulate other genes throughout the body.
The key aspects examined are listed below:
| What Is Analysed | What It Means |
|---|---|
| Point mutations | Single-letter changes in the DNA sequence of the MECP2 gene, detected by Sanger sequencing |
| Deletions and duplications | Missing or extra segments of DNA, detected using a method called MLPA |
| Variant classification | Detected changes are classified as pathogenic (disease-causing), likely pathogenic, or a variant of uncertain significance (VUS) |
Why is a RETT Syndrome (MECP2 Mutation Analysis) Test Done?
A doctor may order this test when a child shows specific developmental changes or when a family history of the condition exists. The sections below explain the key reasons.
Common Symptoms That May Require This Test
The following symptoms are among the most common reasons a doctor may recommend a RETT Syndrome test.
- Stereotypic hand movements such as hand-wringing or hand-squeezing
- Loss of previously acquired purposeful hand movements
- Loss of speech or language skills after a period of normal development
- Difficulty walking or abnormal gait
- Irregular breathing patterns
- Seizures
- Slowed head growth after birth (acquired microcephaly)
Conditions This Test Can Help Detect
This test can help identify a range of conditions, including the following:
- Classic Rett syndrome and atypical or variant Rett syndrome in females
- Mild learning disabilities in females carrying an MECP2 mutation
- MECP2-duplication syndrome in males
- Severe brain disease (encephalopathy) in male newborns related to MECP2 changes
- Non-syndromic or syndromic intellectual disability in males
- Carrier status in family members
How to Prepare and What to Expect
No special preparation is needed for this test. The sections below explain what to expect before and during sample collection.
Do You Need to Fast?
No. Fasting is not required before a RETT Syndrome (MECP2 Mutation Analysis) test. There are no dietary restrictions of any kind.
Practical Tips Before Your Test
Keep the following points in mind before your appointment:
- Bring a detailed clinical history, including the child's symptoms, developmental milestones, previous test results, and family history, as this is required for the test.
- Inform the doctor if the patient has recently received a blood transfusion or bone marrow transplant, as these can introduce donor DNA into the sample.
- No medication changes are needed before the test.
- Consider speaking with a genetic counsellor before testing to understand what the results may mean for your family.
Step-by-Step Procedure
The sample collection process for this test involves the following steps:
- A trained phlebotomist cleans the inner elbow area with an antiseptic solution.
- A small blood sample (2 mL) is drawn from a vein and collected into a lavender-top EDTA tube.
- The tube is labelled with the patient's details and the date of collection.
- The sample is stored at 2 to 8 degrees Celsius and transported to the laboratory under controlled conditions.
- In the laboratory, DNA is extracted from the blood cells, and the MECP2 gene is analysed by Sanger sequencing.
- The findings are reviewed by specialist scientists, and a detailed report is prepared.
Factors That Can Affect Accuracy
The following factors may affect the reliability of the test result:
- Recent blood transfusion or bone marrow transplant, which may introduce donor DNA
- Haemolysis (breakdown of red blood cells in the sample) or an insufficient sample volume
- Somatic mosaicism, a condition where only some body cells carry the mutation, which may reduce detection sensitivity
- Large chromosomal rearrangements that do not change the number of gene copies may not be consistently detected
Understanding Your RETT Syndrome (MECP2 Mutation Analysis) Test Results
Results for this test are reported qualitatively rather than as numbers. Your doctor or genetic counsellor will review the findings alongside the child's clinical symptoms and family history.
| Result | Meaning |
|---|---|
| Negative (no pathogenic variant detected) | No disease-causing change was found in the MECP2 gene |
| Positive (pathogenic or likely pathogenic variant detected) | A disease-causing or probably disease-causing change was found, confirming or strongly supporting a diagnosis of Rett syndrome or a related MECP2 disorder |
| Variant of uncertain significance (VUS) | A change was found, but there is not yet enough evidence to confirm whether it causes disease |
Results are classified in line with American College of Medical Genetics and Genomics (ACMG) recommendations. A negative result does not entirely rule out Rett syndrome, as mutations in other genes such as CDKL5 or FOXG1 may also be responsible.
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
Some factors can influence how results are interpreted.
A mother may carry the MECP2 mutation but show no symptoms due to a process called non-random X-chromosome inactivation, where one X chromosome is preferentially switched off. This can affect carrier screening results within a family. Somatic mosaicism, where the mutation is present in only some body cells, may also reduce detection sensitivity in a blood-based test.
How to Maintain Healthy Levels
Because Rett syndrome is caused by spontaneous genetic mutations, there are no lifestyle changes that prevent it. The following points offer general guidance for families:
- Genetic counselling is recommended for families in which a mutation has been identified, to understand the implications for other family members.
- Early diagnosis supports timely access to supportive therapies, such as physiotherapy, speech therapy, and occupational therapy.
- Keeping detailed records of symptoms and developmental history helps doctors and counsellors provide better guidance.
Lupin Diagnostics RETT Syndrome (MECP2 Mutation Analysis) Test Price and Home Collection
The RETT Syndrome test cost at Lupin Diagnostics starts at ₹7,000, and home sample collection is available across multiple cities in India.
| City | Approximate Price (₹) |
|---|---|
| BHOPAL | 7000 |
| CHENNAI | 7000 |
| HYDERABAD | 7000 |
| KOLKATA | 7000 |
| NAVI MUMBAI | 7000 |
| PUNE | 7000 |
Disclaimer: Prices are indicative and may vary by location. Please confirm the current price at the time of booking.
How to Book
You can book the RETT Syndrome test online by following these steps:
- 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
RETT Syndrome test home collection is available across cities in India through Lupin Diagnostics. All samples are processed in NABL-accredited laboratories staffed by qualified scientists and genetic specialists. Digital reports are accessible via email or WhatsApp once ready.
Frequently Asked Questions
This test examines the MECP2 gene for changes that cause Rett syndrome and related neurological conditions. It helps confirm a diagnosis in children showing developmental regression and can also identify carrier status in family members to support genetic counselling.
The test is primarily recommended for young girls who have shown a period of normal development followed by loss of speech, purposeful hand movements, or walking ability. It may also be ordered for male patients with unexplained severe brain disease or intellectual disability, and for family members of a confirmed case.
Rett syndrome mostly affects females, occurring in approximately 1 in 10,000 to 20,000 live births. It was previously thought to be fatal in males, but rare male patients with MECP2 mutations have been identified. In males, MECP2 changes tend to cause different but equally serious conditions, such as MECP2-duplication syndrome.
Not entirely. MECP2 sequencing detects mutations in approximately 80% of typical Rett syndrome cases. Of those with a normal sequencing result, around 15% may have a deletion or duplication identified by further testing. Mutations in other genes, such as CDKL5 or FOXG1, may account for remaining cases.
Results are typically available within 15 days. Genetic testing requires DNA extraction, sequencing, and detailed analysis by specialist scientists, which takes considerably longer than routine blood tests.
No special preparation is required. There is no need to fast or change any medications. However, you should bring a detailed clinical history, including the child's symptoms and developmental records, as this information is needed along with the sample.
RETT Syndrome (MECP2 Mutation Analysis) Test
