Mitochondrial disorders are complex multisystemic heterogeneous conditions that are often difficult to diagnose. Mitochondrial disorders often manifest with multi-organ symptomatology and can include: seizures, ataxia, peripheral neuropathy, retinopathy, hearing loss, migraines, cardiomyopathy, cardiac conduction defects, abnormalities in intestinal motility, muscle weakness, diabetes, and hypothyroidism.
Mitochondria are cytoplasmic organelles that primarily function to create energy for the cell. Mitochondrial DNA exists within the mitochondria, and is a separate entity from nuclear DNA. To date, greater than fifty mutations have been identified in mitochondrial DNA that are known to be associated with mitochondrial disease. Genetics Center Mitochondrial Panel tests for the more common mitochondrial disorders including: MELAS (Mitochondrial Encephalomyopathy with Lactic Acidosis, and Stroke-like episodes), MERRF (Myoclonic Epilepsy with Ragged Red Fibers), NARP (Neuropathy, Ataxia, and Retinitis Pigmentosa), LHON (Leber Hereditary Optic Neuropathy), Leigh syndrome, Kearns-Sayre syndrome (KSS), progressive external ophthalmoplegia (PEO), and Pearson marrow/pancreas syndrome.
REASONS FOR REFERRAL:
- Confirmation of a clinically suspected mitochondrial disorder.
- Child with unexplained multiple organ system involvement.
- Testing for at-risk relatives.
- Prenatal diagnosis for couples with a significantly increased risk for a specific mitochondrial disorder.
- Regions of mitochondrial DNA are selectively amplified through PCR. Genetics Center analyzes for the following mutations:
- T3271C and A3243G in tRNA-leu (UUR) gene which cause MELAS
- A8344G and T8356C in tRNA-lys gene which cause MERRF
- T8993C and T8993G in subunit 6 of ATPase gene, which cause NARP
- G3460A and G11778A mutations which cause LHON
- Mutation at 8993 responsible for approximately 10% of Leigh syndrome.
- Common deletion of mitochondrial DNA that causes Kearns-Sayre syndrome (KSS), progressive external ophthalmoplegia (PEO) or Pearson marrow/pancreas syndrome.
- 5-7 days
- 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.
211 S. Main Street
Orange, CA 92868
- Molecular Testing Requisition Form (Click Here)
- Molecular Diagnostic Consent Form:
This interpretation is based on the clinical and family information provided and the current understanding of the mitochondrial molecular genetics. A negative result does not completely exclude the possibility that the tested individual carries a rare unexamined mitochondrial DNA mutation, or that one of the examined mutation(s) may be found in another tissue type. If a mitochondrial DNA disorder is still strongly suspected, this analysis is recommended to be repeated on a muscle biopsy sample.
- CPT’s: 81401, G0452