Epilepsia partialis continua associated with a homoplasmic mitochondrial tRNA(Ser(UCN)) mutation

Ann Neurol. 1998 Oct;44(4):700-4. doi: 10.1002/ana.410440420.


Epilepsia partialis continua (EPC) is a rare epileptic syndrome characterized by continuous focal seizures. We report on a 16-year-old girl who died of prolonged pharmacoresistant EPC in whom we identified a 7472insC mutation within the mitochondrial transfer ribonucleic acid (tRNA)(ser(UCN)). Additional symptoms included ataxia, lactic acidosis, myopathy, sensorineural hearing loss, severe headaches, and mental retardation. Quantification revealed 100% mutant mitochondrial DNA (mtDNA) in the patient, 4% in her mother, and none in her half-sister. This highly skewed mtDNA distribution is most improbable (approximately 3 x 10(-30)) if only explained by random genetic drift. Clustering of dysfunctional mitochondria and replicatory advantage of mutant mtDNA may play a role in the rapid segregation towards homoplasmy within one generation.

Publication types

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

MeSH terms

  • Base Sequence
  • Child
  • Epilepsies, Partial / diagnosis
  • Epilepsies, Partial / genetics*
  • Fatal Outcome
  • Female
  • Humans
  • Magnetic Resonance Angiography
  • Magnetic Resonance Imaging
  • Mutation / genetics*
  • Pedigree
  • RNA / genetics*
  • RNA, Mitochondrial
  • RNA, Transfer, Amino Acyl / genetics*
  • Status Epilepticus / genetics*


  • RNA, Mitochondrial
  • RNA, Transfer, Amino Acyl
  • RNA