NARS2 Gene Combined oxidative phosphorylation deficiency type 24 NGS Genetic Test
Short Name: NARS2 Gene COXPD24 NGS Test
Also known as: NARS2 Gene Sequencing Test, COXPD24 Genetic Test, NARS2 Mitochondrial Disorder Test, Combined OXPHOS Deficiency 24 NGS Test, NARS2 Mutation Analysis Test
NARS2 Gene Combined oxidative phosphorylation deficiency type 24 NGS Genetic Test test available at DNA Labs India for ₹20,000. Uses Next Generation Sequencing (NGS), Sanger Confirmation (if required), Bioinformatic Variant Analysis on Blood or Extracted DNA or One Drop Blood on FTA Card samples. Results in 3 to 4 Weeks from sample receipt at the laboratory. Free home collection in 300+ cities across India.
🩺 Medically Reviewed By
Dr SULOCHANA HEMCHANDRA HOLLA
Consultant Medical Geneticist · Reg: 8532
Last reviewed: September 7, 2026
Overview
This test is performed to identify pathogenic mutations in the NARS2 gene responsible for Combined Oxidative Phosphorylation Deficiency Type 24. It serves to confirm a clinical diagnosis in symptomatic individuals, identify carriers within families, guide treatment and management strategies, and assist in genetic counselling and family planning, including prenatal and preimplantation genetic testing options.
- Test Code
- 1946
- CPT Code
- 81479
- ICD Code
- E88.4
- Price
- ₹20,000
- Sample Type
- Blood or Extracted DNA or One Drop Blood on FTA Card
- Result Time
- 3 to 4 Weeks from sample receipt at the laboratory
- Fasting Required
- No
- Method
- Next Generation Sequencing (NGS), Sanger Confirmation (if required), Bioinformatic Variant Analysis
Sample Collection
No special preparation such as fasting is required. Ensure a genetic counselling session has been completed and clinical history of the patient along with a pedigree chart of affected family members is available for the testing laboratory.
Method: Venipuncture / FTA Card Finger Prick
Laboratory Analysis
A venous blood sample of 3-5 mL will be collected in an EDTA vacutainer. Alternatively, a single drop of blood on an FTA card or already extracted DNA may be submitted. The procedure typically takes less than 10 minutes.
Report Delivery
Apply gentle pressure on the venipuncture site with a cotton ball for 3-5 minutes. The sample will be shipped under controlled ambient temperature conditions to the laboratory. Reports will be available within 3 to 4 weeks.
Timeline: 3 to 4 Weeks from sample receipt at the laboratory
Patient Instructions
About This Test
Who Should Get This Test
This test is performed to identify pathogenic mutations in the NARS2 gene responsible for Combined Oxidative Phosphorylation Deficiency Type 24. It serves to confirm a clinical diagnosis in symptomatic individuals, identify carriers within families, guide treatment and management strategies, and assist in genetic counselling and family planning, including prenatal and preimplantation genetic testing options.
How to Prepare
- Blood should be collected in an EDTA (Lavender Top) vacutainer under aseptic conditions.
- If using an FTA card, ensure one complete blood drop is applied and the card is air-dried completely before packaging.
- Already extracted DNA should be shipped at ambient temperature in appropriate tubes with clear labeling.
- Clearly label the sample with patient name, date of birth, and unique identifier.
- Maintain ambient room temperature during transport; do not freeze the sample.
- Ship the sample to DNA Labs India as per the provided shipping instructions in the test kit.
Doctor's Notes
Reviewed by Dr SULOCHANA HEMCHANDRA HOLLA — MBBS, MD (Medical Genetics) · Reg. No. 8532
"COXPD24 is a rare autosomal recessive mitochondrial disorder caused by biallelic pathogenic variants in the NARS2 gene. Early genetic confirmation through NGS-based testing is essential for accurate diagnosis, prognostic counseling, and informed family planning. Carrier screening of parents and at-risk family members is strongly recommended. Prenatal or preimplantation genetic testing may be considered for future pregnancies in confirmed carrier couples."
Last medically reviewed: September 7, 2026
Test Parameters & Specifications
Sample Stability
- Sample received without proper labeling or patient identification
- Hemolyzed, clotted, or insufficient volume of blood sample
- Sample collected in incorrect container (non-EDTA tube)
- Contaminated or degraded DNA sample
- Sample received without accompanying requisition form or clinical history
Understanding Your Results
Pathogenic or Likely Pathogenic Variant(s) Detected
One or more disease-causing variants in the NARS2 gene have been identified. If biallelic (homozygous or compound heterozygous) pathogenic variants are found, this confirms a diagnosis of COXPD24. Genetic counselling and referral to a metabolic specialist are recommended. Carrier testing for family members should be considered.
Variant of Uncertain Significance (VUS) Detected
A variant in the NARS2 gene has been identified whose clinical significance is currently undetermined. Further family studies, functional analysis, or correlation with clinical and biochemical findings may be needed to clarify the variant's role. Continued clinical monitoring and periodic re-evaluation are recommended.
No Pathogenic Variant Detected
No pathogenic or likely pathogenic variants were identified in the NARS2 gene by NGS. This result does not completely exclude COXPD24, as mutations in regulatory or deep intronic regions may not be detected. If clinical suspicion remains high, additional testing including whole exome or whole genome sequencing may be considered.
Carrier Status Identified
A single heterozygous pathogenic variant in the NARS2 gene has been detected. The individual is a carrier of COXPD24 and is typically unaffected. Genetic counselling regarding recurrence risk for offspring and recommendations for partner testing are advised.
Consult a clinical geneticist, metabolic specialist, or pediatric neurologist if your child presents with unexplained developmental delay, muscle weakness, seizures, lactic acidosis, or other signs of mitochondrial dysfunction. Genetic counselling is strongly recommended before and after testing. If you or your partner are known carriers, consult a reproductive genetics specialist for family planning guidance.
Limitations
- ⚠This test does not detect large genomic rearrangements, copy number variants, or deep intronic mutations outside the targeted NARS2 region.
- ⚠Variants of Uncertain Significance (VUS) may be identified and may require further investigation or family studies.
- ⚠A negative result does not completely exclude the possibility of COXPD24 if caused by mutations outside the sequenced regions.
- ⚠This test is specific to the NARS2 gene and does not screen for other mitochondrial or metabolic disorder genes unless separately ordered.
- ⚠Results should always be interpreted in conjunction with clinical presentation, biochemical findings, and family history by a qualified geneticist.
Risks & Considerations
- ●Minor bruising or discomfort at the venipuncture site
- ●Risk of a Variant of Uncertain Significance (VUS) result causing anxiety
- ●Potential psychological or emotional impact of a positive diagnosis
- ●Possible identification of carrier status with implications for family planning
Interfering Factors
- ●Degraded or insufficient DNA quality from the submitted sample
- ●Recent blood transfusion within the past 4 weeks may affect results
- ●Sample contamination during collection or transport
- ●Hemolyzed blood samples may compromise DNA extraction yield
Compare With Similar Tests
| Test | NARS2 Gene Combined oxidative phosphorylation deficiency type 24 NGS Genetic Test | Whole Exome Sequencing (WES) | Mitochondrial DNA Sequencing | Respiratory Chain Enzyme Assay |
|---|---|---|---|---|
| Comparison | NARS2 Gene Combined oxidative phosphorylation deficiency type 24 NGS Genetic Test | WES analyzes all protein-coding genes and can detect mutations in genes beyond NARS2, useful when COXPD24 is suspected but the causative gene is unknown. However, WES is more expensive and may identify incidental findings. | This test analyzes the mitochondrial genome for point mutations and deletions. COXPD24 is caused by nuclear gene (NARS2) mutations, so mtDNA sequencing alone would not detect it. Both tests may be complementary in complex mitochondrial disease workup. | Biochemical testing of respiratory chain enzyme activities in muscle biopsy or fibroblasts can detect combined oxidative phosphorylation deficiency but cannot identify the specific gene involved. Genetic testing is needed for definitive molecular diagnosis. |
Frequently Asked Questions
What is the NARS2 Gene Combined Oxidative Phosphorylation Deficiency Type 24 NGS Genetic Test?
Who should undergo the NARS2 Gene COXPD24 Genetic Test?
What sample is required for the NARS2 Gene COXPD24 NGS Genetic Test?
How long does it take to receive the results?
What is the cost of the NARS2 Gene COXPD24 NGS Genetic Test?
Does DNA Labs India provide raw data files with the genetic test report?
What does a positive result mean?
Can this test be used for prenatal diagnosis?
Is home sample collection available for this test?
What is the inheritance pattern of COXPD24?
What should I do before getting the NARS2 Gene COXPD24 Genetic Test?
Is a negative result sufficient to rule out COXPD24?
Related Tests
Reference Laboratory Services
We serve as a reference laboratory for hospitals and clinics across India. Send samples from your facility with same-day pickup, priority processing, and results delivered through our online portal. Competitive institutional pricing available.
Your Data Privacy
Your medical data is protected under Indian law.
✓ Stored in India: All patient records are stored on servers located in India. No data is transferred outside the country.
✓ DPDP Act Compliant: Under the Digital Personal Data Protection Act 2023, you can request deletion of your records at any time by contacting support.
Book Your Test
Enter your details and we'll connect you within 15 minutes.