Mitochondrial DNA replication and disease: insights from DNA polymerase γ mutations

Cell Mol Life Sci. 2011 Jan;68(2):219-33. doi: 10.1007/s00018-010-0530-4. Epub 2010 Oct 8.

Abstract

DNA polymerase γ (pol γ), encoded by POLG, is responsible for replicating human mitochondrial DNA. About 150 mutations in the human POLG have been identified in patients with mitochondrial diseases such as Alpers syndrome, progressive external ophthalmoplegia, and ataxia-neuropathy syndromes. Because many of the mutations are described in single citations with no genotypic family history, it is important to ascertain which mutations cause or contribute to mitochondrial disease. The vast majority of data about POLG mutations has been generated from biochemical characterizations of recombinant pol γ. However, recently, the study of mitochondrial dysfunction in Saccharomyces cerevisiae and mouse models provides important in vivo evidence for the role of POLG mutations in disease. Also, the published 3D-structure of the human pol γ assists in explaining some of the biochemical and genetic properties of the mutants. This review summarizes the current evidence that identifies and explains disease-causing POLG mutations.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, N.I.H., Intramural
  • Review

MeSH terms

  • Animals
  • DNA Polymerase gamma
  • DNA Replication*
  • DNA, Mitochondrial* / genetics
  • DNA-Directed DNA Polymerase* / chemistry
  • DNA-Directed DNA Polymerase* / genetics
  • Disease Models, Animal
  • Humans
  • Mice
  • Mitochondria* / genetics
  • Mitochondrial Diseases / genetics
  • Models, Molecular
  • Mutation
  • Saccharomyces cerevisiae
  • Sequence Analysis, DNA

Substances

  • DNA, Mitochondrial
  • DNA Polymerase gamma
  • DNA-Directed DNA Polymerase