New mitochondrial DNA mutations in tRNA associated with three severe encephalopamyopathic phenotypes: neonatal, infantile, and childhood onset

Neurogenetics. 2012 Aug;13(3):245-50. doi: 10.1007/s10048-012-0322-0. Epub 2012 May 26.


The reported cases showed clinical, biochemical, histopathological, and molecular features lending support to the hypothesis of a pathogenic effect of the detected mutations. Case 1 was a neonatal presentation who showed multiple mitochondrial respiratory chain enzyme defects in muscle associated with a new homoplasmic m.5514A > G transition in the tRNA(Trp) gene. Case 2 was a late infantile presentation who also showed mitochondrial respiratory chain enzyme deficiencies in muscle together with a new m.1643A > G tRNA(Val) mutation in homoplasmy. Case 3 showed a MERRF phenotype presented in childhood associated with the once previously reported m.15923A > G mutation in heteroplasmy in all the tissues studied.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Base Sequence
  • Child
  • Child, Preschool
  • DNA, Mitochondrial / genetics*
  • Electron Transport
  • Humans
  • Infant, Newborn
  • MERRF Syndrome / genetics*
  • Mitochondria / metabolism
  • Mitochondrial Diseases / genetics*
  • Molecular Sequence Data
  • Muscles / pathology
  • Mutation
  • Nucleic Acid Conformation
  • Phenotype
  • RNA, Transfer / genetics*


  • DNA, Mitochondrial
  • RNA, Transfer