Mitochondrial DNA deletion in a patient with mitochondrial myopathy, lactic acidosis, and stroke-like episodes (MELAS) and Fanconi's syndrome

Pediatr Neurol. 1995 Jul;13(1):69-72. doi: 10.1016/0887-8994(95)00082-q.


Large-scale mitochondrial DNA deletion was found in a 5-year-old girl with mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) and Fanconi's syndrome. Muscle biopsy disclosed ragged-red fibers and cytochrome c oxidase negative fibers. Respiratory chain studies were normal. Southern blot analysis demonstrated a 10.5-Kb heteroplasmic deletion in both muscle and blood. Deleted genomes represented 40% of total mitochondrial DNA in muscle and 63% in blood. There was no evidence of point mutations characteristic of MELAS. We suggest that not only patients with progressive external ophthalmoplegia syndromes, but also those with defined syndromes [e.g., MELAS or myoclonic epilepsy and ragged-red fibers (MERRF)] without characteristic point mutations, be screened for mitochondrial DNA deletions.

Publication types

  • Case Reports
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biopsy
  • Child, Preschool
  • Chromosome Deletion*
  • Chromosome Mapping
  • DNA, Mitochondrial / genetics*
  • Fanconi Syndrome / genetics*
  • Female
  • Genetic Testing
  • Humans
  • MELAS Syndrome / genetics*
  • MERRF Syndrome / genetics
  • Mitochondrial Encephalomyopathies / genetics*
  • Muscle, Skeletal / pathology
  • Point Mutation
  • RNA, Transfer, Leu / genetics


  • DNA, Mitochondrial
  • RNA, Transfer, Leu