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GTR Home > Conditions/Phenotypes > MELAS syndrome

MELAS syndrome

Synonyms
Juvenile myopathy, encephalopathy, lactic acidosis, stroke; Mitochondrial encephalomyopathy lactic acidosis and stroke-like episodes
Modes of inheritance
Mitochondrial inheritance (Orphanet)
Not genetically inherited (Orphanet)

Summary

MELAS (mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes) is a multisystem disorder with protean manifestations. The vast majority of affected individuals develop signs and symptoms of MELAS between ages two and 40 years. Common clinical manifestations include stroke-like episodes, encephalopathy with seizures and/or dementia, muscle weakness and exercise intolerance, normal early psychomotor development, recurrent headaches, recurrent vomiting, hearing impairment, peripheral neuropathy, learning disability, and short stature. During the stroke-like episodes neuroimaging shows increased T2-weighted signal areas that do not correspond to the classic vascular distribution (hence the term "stroke-like"). Lactic acidemia is very common and muscle biopsies typically show ragged red fibers. [from GeneReviews]

Available tests

37 tests are in the database for this condition.

Check Related conditions for additional relevant tests.

Clinical tests (37 available)

Molecular Genetics Tests

Genes See tests for all associated and related genes

  • Also known as: COI, MTCO1, COX1
    Summary: mitochondrially encoded cytochrome c oxidase I

  • Also known as: COII, MTCO2, COX2
    Summary: mitochondrially encoded cytochrome c oxidase II

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

  • Also known as: MTCYB, CYTB
    Summary: mitochondrially encoded cytochrome b

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

  • 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: MTTC, TRNC
    Summary: mitochondrially encoded tRNA cysteine

  • Also known as: , TRNF
    Summary: mitochondrially encoded tRNA phenylalanine

  • 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: MTTQ, TRNQ
    Summary: mitochondrially encoded tRNA glutamine

  • Also known as: MTTS1, TRNS1
    Summary: mitochondrially encoded tRNA serine 1 (UCN)

  • Also known as: MTTS2, TRNS2
    Summary: mitochondrially encoded tRNA serine 2 (AGU/C)

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

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

Clinical features

Help
Imported from Human Phenotype Ontology (HPO)

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