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GTR Home > Conditions/Phenotypes > Mitochondrial DNA-Associated Leigh Syndrome and NARP


Excerpted from the GeneReview: Mitochondrial DNA-Associated Leigh Syndrome Spectrum
Mitochondrial DNA-associated Leigh syndrome spectrum (mtDNA-LSS) is part of a continuum of progressive neurodegenerative disorders caused by abnormalities of mitochondrial energy generation, which includes the overlapping phenotypes mtDNA-associated Leigh syndrome and mtDNA-associated Leigh-like syndrome. Mitochondrial DNA-LSS is characterized by onset of manifestations typically between ages three and 12 months, often following an intercurrent illness (usually viral) or metabolic challenge (vaccinations, surgery, prolonged fasting). Decompensation (often with elevated lactate levels in blood and/or cerebrospinal fluid) is typically associated with developmental delay and/or regression. Neurologic features include hypotonia, spasticity, seizures, movement disorders, cerebellar ataxia, and peripheral neuropathy. Brain stem dysfunction may manifest with respiratory symptoms, swallowing difficulties, ophthalmoparesis, and abnormalities in thermoregulation. Extraneurologic manifestations may include poor weight gain, cardiomyopathy, and conduction defects. Up to 50% of individuals die by age three years, most often from respiratory or cardiac failure.

Available tests

15 tests are in the database for this condition.

Check Related conditions for additional relevant tests.

Genes See tests for all associated and related genes

  • Also known as: ATPase6, MTATP6, ATP6
    Summary: mitochondrially encoded ATP synthase 6

  • Also known as: COIII, MTCO3, COX3
    Summary: mitochondrially encoded cytochrome c oxidase III

  • Also known as: MTND1, ND1
    Summary: mitochondrially encoded NADH dehydrogenase 1

  • Also known as: MTND2, ND2
    Summary: mitochondrially encoded NADH dehydrogenase 2

  • Also known as: MTND3, ND3
    Summary: mitochondrially encoded NADH dehydrogenase 3

  • Also known as: MTND4, ND4
    Summary: mitochondrially encoded NADH dehydrogenase 4

  • Also known as: MTND5, ND5
    Summary: mitochondrially encoded NADH dehydrogenase 5

  • Also known as: MTND6, ND6
    Summary: mitochondrially encoded NADH dehydrogenase 6

  • Also known as: MTTI, TRNI
    Summary: mitochondrially encoded tRNA isoleucine

  • Also known as: MTTK, TRNK
    Summary: mitochondrially encoded tRNA lysine

  • Also known as: MTTL1, TRNL1
    Summary: mitochondrially encoded tRNA leucine 1 (UUA/G)

  • Also known as: MTTL2, TRNL2
    Summary: mitochondrially encoded tRNA leucine 2 (CUN)

  • Also known as: MTTV, TRNV
    Summary: mitochondrially encoded tRNA valine

  • Also known as: MTTW, TRNW
    Summary: mitochondrially encoded tRNA tryptophan

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