A novel mutation in the mitochondrial tRNA(Pro) gene associated with late-onset ataxia, retinitis pigmentosa, deafness, leukoencephalopathy and complex I deficiency

Eur J Hum Genet. 2009 Aug;17(8):1092-6. doi: 10.1038/ejhg.2009.12. Epub 2009 Feb 18.


We present a patient with ataxia, retinitis pigmentosa, dysarthria, neurosensorial deafness, nystagmus and leukoencephalopathy. A novel heteroplasmic G to A transition at nucleotide 15 975 was found, affecting the T arm of the mitochondrial (mt) tRNA(Pro) gene. A biochemical analysis of respiratory chain enzymes in muscle revealed isolated complex I deficiency. This is the fourth pathogenic tRNA(Pro) point mutation to be associated with an mt disorder. The result highlights the importance of molecular dissection of mtDNA in patients with defined mt disorder and confirms the clinical and biochemical heterogeneity associated with tRNA(Pro) mutations.

Publication types

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

MeSH terms

  • Age of Onset
  • Ataxia / complications
  • Ataxia / epidemiology
  • Ataxia / genetics*
  • Base Sequence
  • Brain Diseases / complications
  • Brain Diseases / genetics*
  • Deafness / complications
  • Deafness / genetics*
  • Electron Transport Complex I / deficiency
  • Electron Transport Complex I / genetics*
  • Female
  • Genes, Mitochondrial
  • Hearing Loss, Sensorineural / genetics
  • Humans
  • Middle Aged
  • Molecular Sequence Data
  • Mutation, Missense
  • Nucleic Acid Conformation
  • Nystagmus, Congenital / complications
  • Nystagmus, Congenital / genetics
  • Pedigree
  • RNA, Transfer, Pro / genetics*
  • Retinitis Pigmentosa / complications
  • Retinitis Pigmentosa / genetics*


  • RNA, Transfer, Pro
  • Electron Transport Complex I