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The A8344G mutation in mitochondrial DNA associated with stroke-like episodes and gastrointestinal dysfunction

Kurenai Tanji1, Josep Gamez, Carles Cervera

  • 1Department of Pathology of the College of Physicians and Surgeons of Columbia University, New York, NY 10032, USA.

Acta Neuropathologica
|December 10, 2002
PubMed

Insights

A8344G mutation in mitochondrial DNA (mtDNA) caused encephalo-entero-myopathy with stroke-like episodes and paralytic ileus. This case highlights an unusual presentation of the common MERRF mutation.

Area of Science:

  • Genetics
  • Neurology
  • Mitochondrial Biology

Background:

  • Mitochondrial DNA (mtDNA) mutations are linked to various neuromuscular disorders.
  • The A8344G mutation in the tRNA(Lys) gene is typically associated with Myoclonic Epilepsy with Ragged Red Fibers (MERRF).

Observation:

  • A patient presented with encephalo-entero-myopathy, including mitochondrial myopathy, lipomatosis, hearing loss, stroke-like episodes, and paralytic ileus.
  • The patient lacked the canonical MERRF features of myoclonus, epilepsy, or ataxia.

Findings:

  • Genetic analysis confirmed the A8344G mtDNA mutation in multiple tissues.
  • Biochemical and histochemical studies revealed selective cytochrome c oxidase (COX) deficiency in the brain and small intestine.
  • COX deficiency in the small intestine suggests a role in the pathogenesis of paralytic ileus.

Implications:

  • This case demonstrates a rare and severe clinical phenotype associated with the A8344G mtDNA mutation.
  • The findings expand the known spectrum of clinical manifestations for this common mtDNA mutation.
  • Highlights the importance of considering mitochondrial dysfunction in unexplained neurological and gastrointestinal disorders.

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