Spinocerebellar Ataxia (SCA - Single Form) Test
About Spinocerebellar Ataxia (SCA - Single Form) Test
| Field | Value |
|---|---|
| Also Known As | SCA single gene test, spinocerebellar ataxia single type analysis, SCA genetic test (Single Form) |
| Sample Type | Peripheral blood (EDTA tube) |
| Fasting Required | No fasting required |
| Report Time | 12 days |
| Recommended For | Males and females of all ages with ataxia symptoms or a family history of SCA |
| Price | Starting at ₹4,200 |
What is a Spinocerebellar Ataxia (SCA - Single Form) Test?
The spinocerebellar ataxia test is a specialised genetic test that analyses a blood sample to detect mutations in a single gene associated with one specific type of spinocerebellar ataxia (SCA). SCA is an inherited condition that progressively damages the cerebellum, the part of the brain that controls balance and movement. Doctors prescribe this test when a patient shows symptoms of cerebellar ataxia or has a known family history of the condition. It is also known as the SCA Single Gene Test or Spinocerebellar Ataxia Single Type Analysis.
What Does a Spinocerebellar Ataxia (SCA - Single Form) Test Measure?
This test examines DNA extracted from a blood sample to identify genetic abnormalities linked to a specific SCA type. The laboratory uses a method called MLPA (Multiplex Ligation-dependent Probe Amplification) to detect changes at the gene level.
The key things this test analyses are listed below.
| What Is Measured | What It Means |
|---|---|
| CAG trinucleotide repeat count | Counts the number of times a specific DNA sequence (CAG) repeats in the gene; an unusually high number causes disease |
| Specific gene mutation status | Checks whether the gene tested (such as ATXN1, ATXN2, ATXN3, CACNA1A, or ATXN7) carries a disease-causing expansion |
| CAT interruption status (for SCA1) | Assesses a secondary feature within the repeat region that helps determine whether certain borderline repeat counts are likely to cause disease |
Why is a Spinocerebellar Ataxia (SCA - Single Form) Test Done?
A doctor may order this spinocerebellar ataxia test for a patient who shows neurological symptoms or has a relevant family history. Below are the main reasons this test is requested.
Common Symptoms That May Require This Test
The following symptoms are among the most frequent reasons a doctor recommends this test.
- Progressive difficulty with balance and coordination (ataxia)
- Unsteady walking or gait problems
- Slurred speech or difficulty swallowing
- Rapid, involuntary eye movements (nystagmus)
- Weakness in the muscles that control eye movement (ophthalmoplegia)
- Muscle stiffness (spasticity)
Conditions This Test Can Help Detect
The SCA genetic test (Single Form) helps identify or confirm the following conditions.
- Spinocerebellar ataxia (an inherited, progressive neurodegenerative condition affecting movement and coordination)
- A specific SCA subtype, selected based on the patient's symptoms and family history (over 40 distinct genetic types of SCA have been identified)
- Autosomal dominant cerebellar ataxia in patients where non-genetic causes have already been ruled out
How to Prepare and What to Expect
No special preparation is needed for the spinocerebellar ataxia test. The steps and tips below will help you attend your appointment confidently.
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
Keep the following points in mind before your test.
- Bring a detailed clinical history including your symptoms, previous test results, and family history, as this is required for the test.
- Inform the collection staff if you have had a bone marrow transplant or a recent blood transfusion, as this may affect the reliability of results.
- Seek genetic counselling before testing to understand what the results may mean for you and your family.
- Make sure the sample is not frozen or clotted before it reaches the laboratory; alert the phlebotomist if there are any delays.
Step-by-Step Procedure
Here is what happens during and after sample collection.
- A certified phlebotomist cleans the vein in your arm with an antiseptic and draws approximately 2 mL of blood.
- The blood is collected in a lavender-top EDTA tube (a tube containing an anticoagulant to prevent clotting).
- The tube is gently inverted several times to mix the blood with the anticoagulant.
- The sample is labelled with your details and stored at a refrigerated temperature (2 to 8 degrees Celsius) before dispatch.
- The sample is transported to the laboratory, where MLPA analysis is performed to examine the relevant gene.
- Results are reviewed by a qualified specialist and made available within 12 days.
Factors That Can Affect Accuracy
The following factors may reduce the reliability of test results.
- Frozen or severely haemolysed (damaged) blood samples
- Clotted blood specimens
- Prior allogeneic bone marrow transplant (where the donor's DNA may be detected instead of the patient's own)
- Incorrect sample labelling
- Insufficient clinical history provided at the time of testing
Understanding Your Spinocerebellar Ataxia (SCA - Single Form) Test Results
Your results will show the number of CAG repeats detected in the specific gene tested. A qualified doctor or genetic counsellor should review these findings alongside your full clinical picture. Reference ranges differ by SCA type; examples for the most common types are shown below.
| SCA Type | Gene | Normal Range (CAG Repeats) | Pathogenic Range (CAG Repeats) |
|---|---|---|---|
| SCA1 | ATXN1 | 6 to 35 CAG repeats | 39 or more (without CAT); 45 or more interrupted repeats |
| SCA2 | ATXN2 | 14 to 31 CAG repeats | 35 or more |
| SCA3 | ATXN3 | 12 to 44 CAG repeats | 60 to 87 |
| SCA6 | CACNA1A | 4 to 18 CAG repeats | 20 to 33 |
| SCA7 | ATXN7 | 7 to 27 CAG repeats | 37 or more |
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.
A result within the normal range means no disease-causing expansion was detected in the tested gene. A result above the pathogenic threshold confirms the presence of the mutation associated with that specific SCA type. A negative result does not fully exclude ataxia, as other genetic causes not covered by this single-form test may be present.
Can change in lifestyle improve test results?
Because this is a genetic test, the result reflects your DNA and will not change with lifestyle. The following general wellness steps can support your overall health and quality of life.
- Maintain regular physical activity as tolerated; exercise supports muscle function and overall well-being.
- Eat a balanced diet to support general health.
- Consult with a genetic counsellor after receiving your results to understand next steps and the implications.
Lupin Diagnostics Spinocerebellar Ataxia (SCA - Single Form) test price and home collection
The Spinocerebellar Ataxia test is available at Lupin Diagnostics starting at ₹4,200, with home sample collection available across India.
| City | Approximate Price ( ₹) |
|---|---|
| BHOPAL | 4200 |
| CHENNAI | 4200 |
| HYDERABAD | 4200 |
| KOLKATA | 4200 |
| NAVI MUMBAI | 4200 |
| PUNE | 4200 |
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 spinocerebellar ataxia test online.
- 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
Lupin Diagnostics offers home sample collection for the spinocerebellar ataxia test across multiple cities in India. All samples are processed in NABL-accredited laboratories. Your digital report is shared securely via email or WhatsApp once ready.
Frequently Asked Questions
This is a genetic blood test that detects the number of CAG trinucleotide repeats in a single gene linked to one specific type of spinocerebellar ataxia. It helps confirm or exclude a particular SCA subtype based on your symptoms and family history. The test uses MLPA, a reliable molecular method for identifying gene-level changes.
No, fasting is not required. You can eat and drink as normal before your appointment. The test analyses DNA from your blood, which is not affected by food or drink intake.
A small volume of blood (2 ml) is drawn from a vein in your arm and collected into an EDTA (lavender-top) tube. The procedure takes only a few minutes and can be done at home through Lupin Diagnostics' home collection service.
The turnaround time for this test is 12 days. Because the test involves detailed molecular analysis, the longer processing time is normal for this type of specialised genetic test.
This test is recommended for individuals who show symptoms such as progressive balance problems, an unsteady gait, or speech difficulties, particularly those with a family history suggesting an inherited form of ataxia. It may also be ordered when a doctor has ruled out non-genetic causes of ataxia.
A positive result confirms that the tested gene carries a disease-causing expansion linked to a specific type of SCA. It does not mean symptoms will worsen immediately. Your doctor or genetic counsellor will explain what the result means for your health and for other family members who may be at risk.
The test cannot predict an exact age of onset. However, a larger number of CAG repeats is generally associated with earlier symptom onset and a more severe clinical course. A genetic counsellor can help you understand what your specific result may mean in terms of disease course.
Spinocerebellar Ataxia (SCA - Single Form) Test
