The Use of PNAs and Their Derivatives in Mitochondrial Gene Therapy

  • Paul M. Smith
  • Günther F. Ross
  • Theresa M. Wardell
  • Robert W. Taylor
  • Douglass M. Turnbull
  • Robert N. Lightowlers
Part of the Medical Intelligence Unit book series (MIUN)


Human mitochondria contain their own genome, mtDNA. This small molecule encodes 24 RNA species and 13 polypeptides, which are essential components of the mitochondrial respiratory chain. The mitochondrial genome is present in hundreds or thousands of copies in each cell and is believed to turnover throughout the life of the cell. Defects of the mitochondrial genome (mtDNA) cause a variety of multisystemic disorders routinely affecting the muscle and nervous system. There is currently no effective treatment for patients with defects of the mitochondrial genome. In many patients, defective cells harbour two sub-populations of mtDNA (a situation termed heteroplasmy), one being normal, the other containing the pathogenic mutation. The mutated copy is often recessive, with biochemical and clinical defects only becoming apparent when the levels of mutated mtDNA outweigh the normal copies. It has therefore been postulated that by selectively preventing replication of the mutated mtDNA, the normal copy will propagate, restoring biochemical function. The search has therefore been on during recent years to identify an antigenomic molecule that will fulfil this criterion. Following evidence that peptide nucleic acids could selectively inhibit replication of templates carrying a known pathogenic mtDNA mutation in vitro, we report on the progress of this approach and the various modifications that are now being used to improve the efficacy of PNA-based antigenomic inhibition.


Mitochondrial Genome Peptide Nucleic Acid Lipophilic Cation Peptide Nucleic Acid Oligomer Peptide Nucleic Acid Molecule 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© and Kluwer Academic / Plenum Publishers 2006

Authors and Affiliations

  • Paul M. Smith
    • 1
  • Günther F. Ross
    • 1
  • Theresa M. Wardell
    • 1
  • Robert W. Taylor
    • 1
  • Douglass M. Turnbull
    • 1
  • Robert N. Lightowlers
    • 2
  1. 1.Mitochondrial Research Group School of Neurology, Neurobiology and PsychiatryUniversity of Newcastle upon TyneNewcastle upon TyneUK
  2. 2.Department of NeurologyUniversity of Newcastle upon Tyne Medical SchoolNewcastle upon TyneUK

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