Chromosomal Microarray 750K Test: Booking, Price, and Results
About Chromosomal Microarray 750K Test: Booking, Price, and Results
| Field | Value |
|---|---|
| Also Known As | CMA 750K, Chromosomal Microarray Analysis, CytoScan 750K, SNP Microarray, Molecular Karyotype, aCGH (array Comparative Genomic Hybridisation) |
| Sample Type | Venous blood (3 to 5 mL in EDTA tube); prenatal samples: amniotic fluid, chorionic villus sampling (CVS), or products of conception (POC) |
| Fasting Required | No fasting required |
| Report Time | 10 to 14 working days |
| Recommended For | Children and adults with unexplained developmental delays, intellectual disability, autism spectrum disorders, or congenital anomalies; prenatal cases with foetal structural abnormalities |
| Price | Starting at ₹16,000 |
What Is a Chromosomal Microarray 750K Test?
The Chromosomal Microarray 750K test is a high-resolution genetic test that scans the entire genome for missing or extra segments of DNA. It is also called a molecular karyotype, and goes by alternate names such as CMA 750K, SNP Microarray, and aCGH. Doctors typically order it for children or adults with unexplained developmental delays, intellectual disability, or birth defects when routine tests have not provided a diagnosis. A small blood sample is all that is needed in most cases.
What Does a Chromosomal Microarray 750K Test Measure?
The Chromosomal Microarray 750K platform uses more than 2 million copy number probes alongside approximately 750,000 SNP (single-nucleotide polymorphism) probes to examine the entire genome in one go. The following are the key things the test analyses:
| What Is Measured | What It Means |
|---|---|
| Copy Number Variants (CNVs) | Detects deleted (missing) or duplicated (extra) segments of DNA across all chromosomes |
| Aneuploidy | Identifies whole chromosomes that are missing or present in extra copies, such as trisomy (three copies) or monosomy (one copy) |
| Regions of Homozygosity (ROH) | Flags areas where both copies of a chromosome look identical, which may suggest uniparental disomy (both copies inherited from one parent) |
| Microdeletions and Microduplications | Identifies very small chromosomal imbalances that are too tiny to be seen under a standard microscope |
Why Is a Chromosomal Microarray 750K Test Done?
A doctor may request this test when a patient's symptoms suggest a genetic cause that routine tests have not explained.
Common Symptoms That May Require This Test
The following symptoms often lead a clinician to recommend a Chromosomal Microarray 750K test:
- Unexplained developmental delay or regression of milestones
- Intellectual disability without a known cause
- Speech or language delay that is not explained by hearing loss
- Autism spectrum behaviours or features
- Unusual physical features (described medically as dysmorphic features)
- Seizures with no clear cause
- Multiple birth defects affecting different organ systems
Conditions This Test Can Help Detect
The test can help identify a range of genetic conditions, including:
- Developmental delay, intellectual disability, and autism spectrum disorders
- Defined microdeletion and microduplication syndromes such as DiGeorge syndrome, Williams-Beuren syndrome, Prader-Willi or Angelman syndrome, and 1p36 deletion syndrome
- Chromosomal aneuploidy, including Down syndrome (trisomy 21), Edwards syndrome (trisomy 18), and Patau syndrome (trisomy 13)
- Unexplained recurrent pregnancy loss, when the test is performed on the products of conception
Chromosomal Microarray 750K Test During Pregnancy
Prenatal Chromosomal Microarray Analysis is recommended when a foetal structural abnormality is identified during an ultrasound scan and invasive prenatal testing is being carried out. Studies indicate the test can detect clinically significant chromosomal changes in approximately 6% of pregnancies where a structural anomaly is present, even when a routine karyotype appears normal. It is also used in cases of stillbirth or intrauterine foetal demise to identify a possible genetic cause.
How to Prepare and What to Expect
No special preparation is needed for this test, but a few simple steps will help the appointment go smoothly.
Do You Need to Fast?
No fasting is required before a Chromosomal Microarray 750K test. You can eat and drink normally before sample collection.
Practical Tips Before Your Test
Here are some straightforward steps to prepare:
- Continue any prescribed medications unless your doctor has advised otherwise; inform your doctor about all medicines you take.
- Drink plenty of water before the appointment to make the blood draw easier.
- Bring a valid photo ID and any test requisition form (TRF) provided by your doctor.
- Let the phlebotomist know if you have a bleeding disorder or are on blood-thinning medicines.
Step-by-Step Procedure
The sample collection process is quick and straightforward. Here is what to expect:
- A trained phlebotomist will identify a suitable vein, usually in the crook of your arm.
- A small amount of blood (3 to 5 mL) is drawn into a special EDTA collection tube; the whole draw takes about 2 to 3 minutes.
- A cotton pad or bandage is applied to the site immediately after collection to stop any minor bleeding.
- The sample is labelled and dispatched to the laboratory under controlled conditions.
- In the lab, DNA is extracted from your blood, labelled, and applied to the microarray chip for analysis.
- Results are reviewed by a specialist, and a detailed report is prepared, typically within 10 to 14 working days.
Factors That Can Affect Accuracy
Certain factors may influence the reliability of your result:
- Poor sample quality or degraded DNA can affect analysis.
- Low-level mosaicism (where only a small fraction of cells carry an abnormality) may not always be detected.
- Prenatal or products-of-conception samples may be affected by maternal cell contamination.
- The test has defined resolution limits, so very small changes below those limits will not be detected.
Understanding Your Chromosomal Microarray 750K Test Results
Results from this test are categorised rather than expressed as simple numerical values. A genetic specialist or your referring doctor will walk you through the findings. The table below outlines the main result categories:
| Result Category | What It Means |
|---|---|
| Normal | No pathogenic or likely pathogenic copy number variants detected; chromosomal complement is normal with no significant regions of homozygosity |
| Likely Pathogenic | A missing or extra chromosomal segment is identified that is likely to cause health or developmental differences |
| Variant of Uncertain Significance (VUS) | A chromosomal change is detected, but current evidence is insufficient to confirm whether it causes any health problems |
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 few important limitations apply to this test:
- The test cannot detect balanced chromosomal rearrangements such as reciprocal translocations or inversions, where genetic material is rearranged without any net gain or loss.
- Triploidy (three complete sets of chromosomes) cannot be identified by array comparative genomic hybridisation because the extra chromosome set is masked during the analysis process.
- Prenatal and products-of-conception samples carry a small risk of maternal cell contamination, which can affect the accuracy of the result.
How to Maintain Healthy Levels
Since this is a genetic test rather than a routine blood test, "normal levels" are not applicable in the same way. The following steps support a productive outcome after testing:
- Seek genetic counselling before and after receiving results to understand what the findings mean for you and your family.
- Share the report with all relevant specialists so that appropriate follow-up can be arranged.
- If a genetic cause of developmental delay is confirmed, early intervention programmes can make a meaningful difference to outcomes.
Lupin Diagnostics Chromosomal Microarray 750K Test Price and Home Collection
The Chromosomal Microarray 750K test price starts at approximately ₹16,000, and home sample collection is available across major Indian cities.
| City | Approximate Price (₹) |
|---|---|
| Mumbai | ₹16,000 |
| Bangalore | ₹16,000 |
| Chennai | ₹16,000 |
| Hyderabad | ₹16,000 |
| Kolkata | ₹16,000 |
| Pune | ₹16,000 |
Prices are indicative and may vary by location. Please confirm the current price at the time of booking.
How to Book
- 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
Home sample collection for the Chromosomal Microarray 750K test near me is available across cities, with a certified phlebotomist visiting at your chosen time. All samples are processed in NABL-accredited laboratories by experienced specialists. Once ready, digital reports are shared directly via email or WhatsApp.
Frequently Asked Questions
Standard karyotyping can only detect chromosomal changes larger than approximately 5 megabases. The Chromosomal Microarray 750K test detects much smaller deletions and duplications that a conventional karyotype would miss entirely. This gives it a higher diagnostic yield, particularly for developmental disorders where routine karyotyping has returned a normal result.
Results are typically available within 10 to 14 working days from the date the sample reaches the laboratory. Complex cases may occasionally take longer depending on the analysis required.
Yes. Prenatal Chromosomal Microarray Analysis is performed on foetal samples obtained through amniocentesis or chorionic villus sampling (CVS). It is recommended when foetal structural abnormalities are found on an ultrasound scan. The test requires direct foetal tissue and cannot be done from a maternal blood sample alone.
A VUS means a chromosomal change has been detected, but its clinical impact is currently unclear. Your doctor or genetic counsellor may recommend parental testing to determine whether the variant is inherited or new (de novo), which helps clarify its significance.
No. The Chromosomal Microarray 750K test cannot detect balanced chromosomal rearrangements, single-gene mutations, or very low-level mosaicism in all cases. Your doctor may recommend additional tests, such as whole-exome sequencing, if the clinical picture suggests a condition not covered by microarray analysis.
Yes, home collection is available for blood-based microarray testing. A trained phlebotomist will visit your home at a time that suits you, collect the sample, and ensure it is dispatched to the laboratory under proper conditions.
Chromosomal Microarray 750K Test: Booking, Price, and Results
