Mitochondrial Whole Genome Sequencing
Mitochondrial disorders are a clinically heterogeneous group of conditions that are typically the result of mitochondrial respiratory chain dysfunction, which is essential for aerobic metabolism. Mitochondrial disorders can be caused by mutations of mitochondrial DNA or nuclear DNA. Each human cell contains thousands of copies of mitochondrial DNA and usually, all copies are identical genetically, which is referred to as homoplasmy. Individuals with mitochondrial disorders may have a mixture of mutant and normal mitochondrial DNA within each cell, also known as heteroplasmy.
Reasons for Referral
- Indications for mitochondrial DNA whole genome sequencing in the following clinical scenarios:
- Confirmation of a suspected clinical diagnosis of a mitochondrial DNA disorder.
- Mitochondrial DNA disorders caused by specific point mutation(s) are detected by this testing:
- Leber hereditary optic neuropathy (LHON)
- Neurogenic weakness with ataxia and retinitis pigmentosa/Leigh syndrome
- MELAS
- MERRF
- Chronic progressive external ophthalmoplegia
- Cardiomyopathy
- Diabetes and deafness
- Encephalomyopathy
- Nonsyndromic sensorineural deafness
- Amnioglycoside-induced nonsyndromic deafness
- Myopathy
Testing Methods
Evaluation of the entire mitochondrial genome by next-generation sequencing. Heteroplasmy for specific known mutations will be reported as low as a 5% mutant load.
Turn Around Time
14 to 21 days
Specimen Requirements and Shipping/Handling
Blood: A single tube with 1-5 mL whole blood in EDTA (lavender top).
Shipping:
Store blood at 4°C until shipment. Ship at ambient temperature in an insulated container via overnight delivery within 96 hours of collection.
Send Specimen(s) to:
211. S Main Street
Suite AA
Orange, CA 92868
Tel: (714)288-3500
Required Forms
Test Limitations
The result of this testing should always be interpreted with available information about the patient’s clinical presentation and family history. A negative result reduces but does not completely exclude the possibility that the tested individual could have a mitochondrial disorder. This assay does not detect deletions, duplications or depletion of the mitochondrial genome. Nuclear genes are not tested in this assay. Genetics Center offers a separate panel for Amnioglycoside-induced nonsyndromic deafness [click here] for further details.
CPT Codes
CPT’s: 81479, G0452