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

• Published in: Pediatric neurology 1995-07, Vol.13 (1), p.69-72
• Main Authors: Campos, Yolanda, Garcia-Silva, Teresa, Barrionuevo, Carlos R., Cabello, Ana, Muley, Rafael, Arenas, Joaquin
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Biopsy; Child, Preschool; Chromosome Deletion; Chromosome Mapping; Diseases of striated muscles. Neuromuscular diseases; DNA, Mitochondrial - genetics; Fanconi Syndrome - genetics; Female; Genetic Testing; Humans; Medical sciences; MELAS Syndrome - genetics; MERRF Syndrome - genetics; Mitochondrial Encephalomyopathies - genetics; Muscle, Skeletal - pathology; Neurology; Point Mutation; RNA, Transfer, Leu - genetics
• ISSN: 0887-8994; 1873-5150
• 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.