Mitochondrial DNA defects in Brazilian patients with chronic progressive external ophthalmoplegia

Mitochondrial DNA defects in Brazilian patients with chronic progressive external ophthalmoplegia

Autor Kiyomoto, B. H. Google Scholar
Tengan, C. H. Google Scholar
Moraes, C. T. Google Scholar
Oliveira, ASB Google Scholar
Gabbai, A. A. Google Scholar
Instituição UNIV MIAMI
Universidade Federal de São Paulo (UNIFESP)
Resumo We report herein on eleven Brazilian patients with mitochondrial DNA (mtDNA) deletions, found among thirteen patients with chronic progressive external ophthalmoplegia (CPEO) and ragged-red fibers (RRF). the molecular data was correlated with the morphological and clinical findings. the muscle biopsies were studied by histochemistry, immunohistochemistry and DNA analysis. Muscle mtDNA deletions were mapped and quantitated by Southern blot analysis, polymerase chain reaction and sequencing. of the eleven patients, ten had CPEO without multisystemic involvement and one had Kearns-Sayre syndrome. Three patients had multiple deletions, two of them with no apparent family history. Eight patients showed heteroplasmic single deletions, ranging in length from 2309 to 7566 bp; three of them had the same 'common deletion' of 4977 bp. the proportion of deleted mtDNA ranged from 14 to 89%. Immunohistochemical studies revealed decreased reactivity with the mtDNA-encoded subunit II of cytochrome c oxidase (COX) in all patients, but preserved activity with the nuclear-encoded COX subunit IV in COX-deficient fibers. Two cases presented a few COX-negative fibers with reduced COX IV immunostaining. We found a high frequency of mtDNA deletions in Brazilian patients with CPEO. There was no correlation between clinical severity, morphological findings and the size or amount of the mutated mtDNA in muscle, suggesting that there are still unknown factors influencing the disease phenotype. (C) 1997 Elsevier Science B.V.
Assunto mitochondrial DNA
mitochondrial myopathy
Kearns-Sayre syndrome
Idioma Inglês
Data 1997-11-25
Publicado em Journal of the Neurological Sciences. Amsterdam: Elsevier B.V., v. 152, n. 2, p. 160-165, 1997.
ISSN 0022-510X (Sherpa/Romeo, fator de impacto)
Editor Elsevier B.V.
Extensão 160-165
Direito de acesso Acesso restrito
Tipo Artigo
Web of Science WOS:A1997YJ29800008

Mostrar registro completo

Arquivos deste item

Arquivos Tamanho Formato Visualização

Não existem arquivos associados a este item.

Este item aparece na(s) seguinte(s) coleção(s)