Impaired complex I assembly in a Leigh syndrome patient with a novel missense mutation in the ND6 gene

Ann Neurol. 2003 Nov;54(5):665-9. doi: 10.1002/ana.10734.


We describe a novel mutation in the ND6 gene (T14487C) in a patient with Leigh syndrome. Biochemical analyses indicated a low complex I activity in the patient's fibroblasts but normal values in muscle and liver. Cybrid clones showed a specific complex I defect that correlates with the mutant heteroplasmy levels. Additionally, we demonstrate an altered mobility and a decrease in the levels of fully assembled complex I in the patient's fibroblasts and cybrids, suggesting that the mutation has a profound effect on complex I assembly and/or stability.

Publication types

  • Case Reports
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cells, Cultured
  • DNA Mutational Analysis
  • DNA, Mitochondrial / genetics*
  • Electron Transport Complex I / genetics*
  • Electron Transport Complex I / metabolism
  • Fibroblasts / physiology
  • Humans
  • Infant
  • Leigh Disease / genetics*
  • Male
  • Mutation, Missense
  • Polymerase Chain Reaction


  • DNA, Mitochondrial
  • Electron Transport Complex I