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GTR Home > Conditions/Phenotypes > Mitochondrial DNA depletion syndrome, myopathic form

Mitochondrial DNA depletion syndrome, myopathic form

Synonyms
MITOCHONDRIAL DNA DEPLETION MYOPATHY, TK2-RELATED; MITOCHONDRIAL DNA DEPLETION SYNDROME 2 (MYOPATHIC TYPE); Mitochondrial DNA depletion syndrome 2; TK2-Related Mitochondrial DNA Depletion Syndrome, Myopathic Form
Modes of inheritance
Autosomal recessive inheritance (Orphanet)

Summary

TK2-related mitochondrial DNA (mtDNA) maintenance defect is a phenotypic continuum that ranges from severe to mild. To date, approximately 107 individuals with a molecularly confirmed diagnosis have been reported. Three main subtypes of presentation have been described: Infantile-onset myopathy with neurologic involvement and rapid progression to early death. Affected individuals experience progressive muscle weakness leading to respiratory failure. Some individuals develop dysarthria, dysphagia, and/or hearing loss. Cognitive function is typically spared. Juvenile/childhood onset with generalized proximal weakness and survival to at least 13 years. Late-/adult-onset myopathy with facial and limb weakness and mtDNA deletions. Some affected individuals develop respiratory insufficiency, chronic progressive external ophthalmoplegia, dysphagia, and dysarthria. [from GeneReviews]

Available tests

78 tests are in the database for this condition.

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Clinical tests (78 available)

Molecular Genetics Tests

Genes See tests for all associated and related genes

  • Also known as: MTDPS2, MTTK, PEOB3, SCA31, TK2-EXT, TK2
    Summary: thymidine kinase 2

Clinical features

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Imported from Human Phenotype Ontology (HPO)

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