Mitochondrial disease testing
With CentoMito® CENTOGENE has designed a special panel for diagnostics of mitochondrial diseases. By targeting nuclear encoded genes as well as mitochondrial encoded genes, this panel provides a comprehensive test in patients with a demonstrated mitochondrial deficiency on biopsy material or a suspicion of mitochondrial disorders based on the patient’s symptoms.
What are mitochondrial diseases?
Mitochondrial diseases are genetic conditions that occur when mitochondria fail to produce enough energy for the cell.
Genetic mutations in the mitochondrial genome, or nuclear genes, encoding proteins that maintain the function of the mitochondria, causing symptoms mainly in the organs where energy consumption is high. These organs are eye, liver, kidney, pancreas, blood, inner ear, colon, skeletal muscle, heart and brain.
Mitochondrial diseases are estimated to affect 1 in 5,000–8,500 people.
Who should get tested for mitochondrial diseases?
- Individuals with clinical symptoms characteristic of a specific mitochondrial disorder such as progressive external ophthalmoplegia, muscle biopsy findings, stroke-like episodes, etc.
- Individuals with any progressive multisystem disorder of unknown etiology
- Individuals with multiple complex neurologic features or a single neurological symptom with other system involvement
- Children presenting with lactic acidosis
- Presymptomatic testing for at-risk family members
The following etiologies were identified in 12 patients: impaired glucose tolerance (58.3%), diabetes mellitus (16.6%), alcohol abuse (8.3%), mitochondrial disease (8.3%), and hereditary neuropathy (8.3%). Genetic…
What tests for diagnostics of mitochondrial diseases are offered by CENTOGENE?
CENTOGENE offers two panels for the diagnostics of mitochondrial diseases:
It includes sequence analysis of 372 nuclear encoded mitochondrial proteins and complete mitochondrial genome, with detection of heteroplasmy down to 15%. Large MT gene deletions are also covered by this panel.
MT-ND1, MT-ND2, MT-CO1, MT-CO2, MT-ATP8, MT-ATP6, MT-CO3, MT-ND3, MT-ND4L, MT-ND4, MT-ND5, MT-ND6, MT-CYB, MT-TF, MT-RNR1, MT-TV, MT-RNR2, MT-TL1, MT-TI, MT-TQ, MT-TM, MT-TW, MT-TA, MT-TN, MT-TC, MT-TY, MT-TS1, MT-TD, MT-TK, MT-TG, MT-TR, MT-TH, MT-TS2, MT-TL2, MT-TE, MT-TT, MT-TP.
Large deletions are also covered.
- Positive result – indicates that a previously understood disease-causing mutation was identified. This result can help the physician to assess the risk of experiencing certain symptoms and indicate the best way how to treat the disease. Positive result may also identify family members at risk of having the mutation, and carrier testing may be recommended.
- Negative result – does not necessarily rule out a mitochondrial disorder, and the patient should be managed according to clinical symptoms. Possible reasons for a negative result could be that the patient may have a mutation in a gene not covered by the testing panel, or it could be a mutation which is not detectable t´with the performed test, or the patient does not have a mitochondrial disorder.
- Variant of unknown clinical significance (VUS) – indicates that we have identified a change in the DNA, but this change is not known to be associated with a disorder. To clarify the clinical significance of the variant, testing other family members may be helpful.