title: Ophthalmoplegia due to mitochondrial DNA disease: the need for genetic diagnosis.
abstract: We describe a patient with chronic progressive external ophthalmoplegia (CPEO) who underwent muscle biopsy for suspected mitochondrial disease. In spite of normal histocytochemical cytochrome c oxidase (COX) activity and respiratory chain enzyme measurements in muscle, subsequent molecular genetic analysis revealed the presence of a single, large-scale deletion of mitochondrial DNA (mtDNA). The case serves to illustrate the importance of pursuing the proposed mitochondrial genetic abnormality, even in patients with normal biopsy findings.
authors.affiliation: School of Neurology, Neurobiology and Psychiatry, The Medical School, Framlington Place, University of Newcastle upon Tyne, Newcastle upon Tyne NE2 4HH, United Kingdom.
authors.forename: Andrew M
authors.initials: AM
authors.lastname: Schaefer
authors.forename: Emma L
authors.initials: EL
authors.lastname: Blakely
authors.forename: Philip G
authors.initials: PG
authors.lastname: Griffiths
authors.forename: Douglass M
authors.initials: DM
authors.lastname: Turnbull
authors.forename: Robert W
authors.initials: RW
authors.lastname: Taylor
mesh_terms: D000328:Adult; D001706:Biopsy; D004272:DNA, Mitochondrial / Q000235:genetics*; D004579:Electron Transport; D003576:Electron Transport Complex IV / Q000378:metabolism; D005260:Female; D005820:Genetic Testing; D006651:Histocytochemistry; D006801:Humans; D028361:Mitochondrial Diseases / Q000235:genetics* / Q000473:pathology*; D017246:Ophthalmoplegia, Chronic Progressive External / Q000235:genetics* / Q000473:pathology*
chemical_list: D004272:DNA, Mitochondrial; D003576:Electron Transport Complex IV