Motor neuron disease in a patient with a mitochondrial tRNAIle mutation

Ann Neurol. 2006 Mar;59(3):570-4. doi: 10.1002/ana.20758.


Objective: Motor neuron disease (MND) is a common neurodegenerative condition for which the underlying cause is uncertain in many patients. We identified a patient with clinical features suggestive of MND but additional cardiac and metabolic symptoms. We wished to determine if the clinical features were due to a mitochondrial DNA mutation.

Methods: The brain and spinal cord were studied using neuropathological techniques and agenetic defect investigated in individual neurons.

Results: There were atypical neuropathological features and genetic studies identified a pathogenic, heteroplasmic mitochondria tRNA(Ile) (4274T>C) mutation.

Interpretation: This case adds to the phenotypic variation seen in mitochondrial DNA disease but also highlights the potential role of mitochondrial dysfunction in the cause of MND.

Publication types

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

MeSH terms

  • Aged
  • DNA Mutational Analysis / methods
  • DNA, Mitochondrial / genetics*
  • Electron Transport Complex IV / metabolism
  • Humans
  • Immunohistochemistry / methods
  • Male
  • Motor Neuron Disease / genetics*
  • Motor Neuron Disease / metabolism
  • Motor Neuron Disease / pathology
  • Motor Neurons / metabolism
  • Motor Neurons / pathology
  • Mutation*
  • RNA, Messenger / biosynthesis
  • RNA, Transfer, Ile / genetics*
  • Reverse Transcriptase Polymerase Chain Reaction / methods
  • Succinate Dehydrogenase / metabolism


  • DNA, Mitochondrial
  • RNA, Messenger
  • RNA, Transfer, Ile
  • Succinate Dehydrogenase
  • Electron Transport Complex IV