Abstract | OBJECTIVE: PATIENT AND METHODS: A 34-year-old patient had been suffering for more than 10 years from progressive visual failure, neurosensorial hearing loss, exercise intolerance, muscle weakness, paresthesia in the lower limbs, and difficulties swallowing. Clinical examination revealed generalized muscle wasting, ptosis, external ophthalmoplegia, and ataxia. Ophthalmologic examination showed dystrophic features in the cornea and retina. In skeletal muscle, morphologic and biochemical studies of the respiratory chain complexes were performed. Polymerase chain reaction, single-strand conformation polymorphism, and direct sequencing were used to screen for mutations in the 22 mitochondrial transfer RNA genes. RESULTS: In skeletal muscle, a significantly decreased catalytic activity of complex I was detected by spectrophotometric analysis and numerous cytochrome c oxidase-negative ragged-red fibers were seen on morphologic examination. A G-to-A substitution 3249 (G3249A) mutation was found in the transfer RNA(Leu) gene of the patient and mutant mitochondrial DNA represented 85% of the total in skeletal muscle but only 45% in leukocytes. The mutation was shown to be present in a small fraction in leukocytes from the unaffected mother and to be absent in leukocytes from the healthy sister. CONCLUSIONS:
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Authors | S Seneca, H Verhelst, L De Meirleir, F Meire, C Ceuterick-De Groote, W Lissens, R Van Coster |
Journal | Archives of neurology
(Arch Neurol)
Vol. 58
Issue 7
Pg. 1113-8
(Jul 2001)
ISSN: 0003-9942 [Print] United States |
PMID | 11448301
(Publication Type: Case Reports, Journal Article, Research Support, Non-U.S. Gov't, Review)
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Chemical References |
- DNA, Mitochondrial
- RNA
- Leucine
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Topics |
- Adult
- Atrophy
- Brain
(pathology)
- DNA, Mitochondrial
(genetics)
- Humans
- Kearns-Sayre Syndrome
(enzymology, genetics, pathology)
- Leucine
(genetics)
- Magnetic Resonance Imaging
- Male
- Mitochondria, Muscle
(enzymology)
- Muscle, Skeletal
(pathology)
- Phenotype
- Point Mutation
- Polymerase Chain Reaction
- Polymorphism, Single-Stranded Conformational
- RNA
(genetics)
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