title: Novel mitochondrial DNA ND5 mutation in a patient with clinical features of MELAS and MERRF.
abstract: BACKGROUND
  The mitochondrial DNA gene encoding subunit 5 of complex I (ND5) has turned out to be a hot spot for mutations associated with mitochondrial encephalomyopathy with lactic acidosis and strokelike episodes (MELAS) and various overlap syndromes.
  
  
  OBJECTIVE
  To describe a novel mutation in the ND5 gene in a young man man with an overlap syndrome of MELAS and myoclonus epilepsy with ragged-red fibers.
  
  
  METHODS
  Case report.
  
  
  METHODS
  A 25-year-old man had recurrent strokes, seizures, and myoclonus. His mother also had multiple strokes. A muscle biopsy specimen showed no ragged-red fibers but several strongly succinate dehydrogenase-reactive blood vessels.
  
  
  RESULTS
  Biochemical analysis showed isolated complex I deficiency and molecular analysis revealed a novel heteroplasmic mutation (G13042A) in the ND5 gene.
  
  
  CONCLUSIONS
  These data confirm that ND5 is a genetic hot spot for overlap syndromes, including MELAS and strokelike and myoclonus epilepsy with ragged-red fibers.
authors.affiliation: Department of Neurology, Columbia University College of Physicians and Surgeons, New York, NY 10032, USA.
authors.forename: Ali B
authors.initials: AB
authors.lastname: Naini
authors.forename: Jiesheng
authors.initials: J
authors.lastname: Lu
authors.forename: Petra
authors.initials: P
authors.lastname: Kaufmann
authors.forename: Richard A
authors.initials: RA
authors.lastname: Bernstein
authors.forename: Michelangelo
authors.initials: M
authors.lastname: Mancuso
authors.forename: Eduardo
authors.initials: E
authors.lastname: Bonilla
authors.forename: Michio
authors.initials: M
authors.lastname: Hirano
authors.forename: Salvatore
authors.initials: S
authors.lastname: DiMauro
mesh_terms: D000328:Adult; D000595:Amino Acid Sequence; D004272:DNA, Mitochondrial / Q000235:genetics*; D042967:Electron Transport Complex I / Q000235:genetics*; D006801:Humans; D017241:MELAS Syndrome / Q000201:enzymology / Q000235:genetics* / Q000473:pathology; D017243:MERRF Syndrome / Q000201:enzymology / Q000235:genetics* / Q000473:pathology; D008297:Male; D024101:Mitochondrial Proteins; D008969:Molecular Sequence Data; D009154:Mutation; D021122:Protein Subunits / Q000235:genetics*; D013385:Succinate Dehydrogenase / Q000235:genetics / Q000378:metabolism
chemical_list: D004272:DNA, Mitochondrial; D024101:Mitochondrial Proteins; D021122:Protein Subunits; D013385:Succinate Dehydrogenase; C481838:MT-ND5 protein, human; D042967:Electron Transport Complex I