CAH Deletion & Duplication Detection: Booking, Price, and Results
About CAH Deletion & Duplication Detection Test
| Field | Value |
|---|---|
| Also Known As | CAH Genetic Test, CYP21A2 Deletion/Duplication Analysis, 21-Hydroxylase Gene Deletion/Duplication Test, CAH Molecular Genetic Test |
| Sample Type | Venous blood (EDTA tube) |
| Fasting Required | No |
| Report Time | 15 Days |
| Recommended For | All ages and genders; newborns with abnormal screening, individuals with suspected CAH, carriers, and families with a CAH history |
| Price | Starting at ₹9,500 |
What Is a CAH Deletion & Duplication Detection Test?
The CAH deletion & duplication detection test is a specialised genetic test that looks for large-scale changes in the CYP21A2 gene. This gene provides instructions for making an enzyme called 21-hydroxylase, which the body needs to produce two essential hormones: cortisol and aldosterone. The test is prescribed for newborns with abnormal screening results, individuals with signs of congenital adrenal hyperplasia (CAH), and family members of known carriers. A blood sample collected from a vein is used for analysis.
What Does a CAH Deletion & Duplication Detection Test Measure?
The CAH deletion & duplication detection test uses a method called MLPA (multiplex ligation-dependent probe amplification) to examine the CYP21A2 gene at a molecular level. It looks for the following types of genetic changes:
| What Is Detected | What It Means |
|---|---|
| CYP21A2 gene deletions | Missing sections of the gene that reduce or stop enzyme production |
| CYP21A2 gene duplications | Extra copies of genetic material within the gene region |
| Chimeric genes | Hybrid, non-functional genes formed when CYP21A2 and its nearby pseudogene recombine abnormally |
| Copy number variations (CNVs) | Changes in how many copies of the gene are present in a cell |
Why Is a CAH Deletion & Duplication Detection Test Done?
This test is used to identify the genetic cause of CAH or to determine whether a person carries a gene change that could be passed to their children. Below are the main reasons a doctor may request it.
Common Symptoms That May Require This Test
A doctor may recommend a CAH deletion & duplication detection test when a patient presents with any of the following signs:
- Salt loss and dehydration in a newborn
- Ambiguous or atypical genital development at birth
- Poor feeding and persistent vomiting in infants
- Unusual or early puberty in children
- Rapid growth spurts beyond what is expected for age
- Excess body or facial hair (hirsutism) in females
- Irregular menstrual cycles or infertility in adult women
Conditions This Test Can Help Detect
This test helps identify or confirm the following conditions:
- Classic CAH due to 21-hydroxylase deficiency (salt-wasting or simple virilising forms)
- Non-classic (late-onset) CAH, a milder form presenting in adolescence or adulthood
- Carrier status, where one copy of a gene change is present, but the person does not have CAH
- CAH-X syndrome, which involves joint hypermobility alongside CAH
CAH Deletion & Duplication Detection During Pregnancy
Genetic testing plays an important role when a pregnancy is at risk of CAH. If both parents are known carriers, this CAH genetic test can be used during pregnancy to check whether the foetus has inherited the condition. Early identification allows medical teams and families to plan care before or immediately after birth. Your doctor or genetic counsellor will advise on the appropriate timing and method for prenatal testing.
How to Prepare and What to Expect
No fasting is required for this test, but a few steps will help ensure the sample is suitable for analysis.
Do You Need to Fast?
No. You can eat and drink as normal before your sample is collected. Fasting does not affect the outcome of this genetic test.
Practical Tips Before Your Test
- Bring a detailed clinical history, including your symptoms, previous test results, and family history of CAH, as this is required for the test.
- Inform your doctor if you have had a recent blood transfusion, as this may affect the DNA analysis.
- Mention all current medications and supplements to your doctor before the test.
- Ensure informed consent is completed and that genetic counselling has been discussed with your care team.
- Wear clothing with short or loose sleeves to make the blood draw easier.
Step-by-Step Procedure
The CAH deletion & duplication detection test procedure involves two samples: a venous blood sample and, in some cases, a bone marrow sample. Your doctor will confirm which is needed. For most patients, only a blood sample is required.
Blood Sample Collection:
- A trained phlebotomist cleans a vein in your arm with an antiseptic wipe.
- A small needle is inserted, and 3 mL of blood is collected into a lavender-top EDTA tube.
- The sample is labelled with your details and stored at 2-8°C for transport.
- The sample is sent to the Lupin Diagnostics specialised genetics laboratory.
- Scientists use the MLPA method to analyse the CYP21A2 gene for deletions, duplications, chimeric genes, and copy number variations.
- A molecular geneticist reviews the findings and prepares your clinical report, which is delivered within 15 days.
Factors That Can Affect Accuracy
- Recent blood transfusions, which may introduce foreign DNA into the sample.
- Poor DNA quality due to an inadequate or degraded sample.
- The high similarity between the CYP21A2 gene and a nearby pseudogene (CYP21A1P), which can make some changes difficult to distinguish.
- Rare variants in the primer binding regions of the gene, which may occasionally cause misleading results.
- Some forms of CAH are caused by changes in other genes, meaning a negative result does not completely rule out the condition.
Understanding Your CAH Deletion & Duplication Detection Results
Your results should always be reviewed with your doctor or a qualified genetic counsellor, who can place the findings in the context of your clinical history and any biochemical tests you have had.
| Parameter | Normal Finding | Abnormal Finding |
|---|---|---|
| CYP21A2 gene copy number | 2 copies (one on each chromosome) | Fewer or more than 2 copies |
| Deletions | Not detected | Detected (pathogenic) |
| Duplications | Not detected | Detected (pathogenic) |
| Chimeric genes | Not detected | Detected |
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
A negative result does not completely rule out CAH. Patients without detectable CYP21A2 gene changes may still have CAH caused by a different enzyme defect. Additionally, the close genetic similarity between CYP21A2 and its pseudogene can lead to some complex rearrangements being missed. Rare primer-binding site variants can occasionally produce false-negative or false-positive findings. Your doctor will combine your genetic result with hormone test data and clinical signs to reach a final diagnosis.
How to Maintain Healthy Levels
- Attend follow-up appointments with an endocrinologist if CAH is confirmed, so that hormone levels can be monitored appropriately.
- Seek genetic counselling to understand what your results mean for you and your family members.
- If you are a carrier, consider discussing family planning options with a specialist before or during pregnancy.
Lupin Diagnostics CAH Deletion & Duplication Detection Price and Home Collection
The CAH deletion & duplication detection test is priced starting at ₹9,500 at Lupin Diagnostics, with home sample collection available in select cities. The indicative city-wise prices are listed below.
| City | Approximate Price (₹) |
|---|---|
| BHOPAL | 8400 |
| CHENNAI | 8400 |
| HYDERABAD | 8400 |
| KOLKATA | 8400 |
| NAVI MUMBAI | 9500 |
| PUNE | 8400 |
Prices are indicative and may vary by location. Please confirm the current price at the time of booking.
How to Book
Booking your CAH deletion & duplication detection test online is straightforward:
- 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 15 days.
Home Collection
Lupin Diagnostics offers home collection for this test across multiple cities. Your sample is collected by a trained phlebotomist and processed in an NABL-accredited laboratory. Once ready, your report is delivered digitally for easy access and sharing with your doctor.
Frequently Asked Questions
This test identifies large-scale genetic changes (deletions and duplications) in the CYP21A2 gene, which cause over 95% of CAH cases. It is used to confirm a CAH diagnosis, identify carriers, and support family planning decisions. Results help doctors understand the genetic basis of the condition in a specific individual.
This test is recommended for newborns with abnormal CAH newborn screening results, children or adults with signs of 21-hydroxylase deficiency, individuals with a family history of CAH, and couples planning a pregnancy where one or both partners are known carriers. Your doctor will advise whether it is appropriate for you.
No fasting is needed. You can eat and drink as you normally would before your blood sample is collected. This genetic test is not affected by food or fluid intake.
Results are typically available within 15 days. The test requires specialised molecular analysis and expert review by genetics professionals, which is why the turnaround time is longer than a routine blood test.
A positive result means a disease-causing genetic change has been found in the CYP21A2 gene. Depending on whether one or both copies of the gene are affected, this may indicate classic CAH, non-classic CAH, or carrier status. Your doctor and a genetic counsellor will explain the implications and next steps.
Yes. Prenatal testing is possible for pregnancies where both parents are known carriers. This allows doctors to determine early whether the foetus is affected. Your obstetrician or genetic counsellor will guide you on the safest approach and timing.
Not always. A negative result means no deletion or duplication was found in the CYP21A2 gene, but some patients have CAH due to other genetic changes or defects in other genes. Your doctor will review your hormone levels and clinical history alongside the genetic result to reach a complete assessment.
CAH Deletion & Duplication Detection: Booking, Price, and Results
