New evidence for the insertion of mitochondrial DNA into the human genome: significance for cancer and aging

Mutat Res. 1992 Sep;275(3-6):227-35. doi: 10.1016/0921-8734(92)90026-l.


We have observed and characterized in detail two cases of mitochondrial DNA fragments which have inserted into the nucleus of HeLa cells. In one case three non-sequential but contiguous regions of mitochondrial DNA with 92% homology to human cytoplasmic mitochondrial DNA inserted into the nuclear genome. In the second case the mitochondrial DNA sequence encoding cytochrome c oxidase subunit III was contiguous with and 5' of exons 2 and 3 of the c-myc oncogene and the chimeric gene was transcribed. Models are presented that describe mechanisms for the transfer of mitochondrial DNA into the nucleus involving fragmentation of mitochondrial DNA through aging and/or oxidative damage, anomalous processing or escape of mitochondrial DNA and RNA fragments from autophagic vacuoles, and insertion of mitochondrial DNA sequences, in some instances after reverse transcription of mitochondrial RNA, into the nuclear genome.

Publication types

  • Research Support, U.S. Gov't, P.H.S.
  • Review

MeSH terms

  • Adult
  • Aging / genetics*
  • Cell Nucleus / physiology
  • Cell Nucleus / ultrastructure
  • DNA Transposable Elements
  • DNA, Mitochondrial / genetics*
  • Genome, Human*
  • HeLa Cells
  • Humans
  • Middle Aged
  • Mitochondria, Heart / ultrastructure
  • Neoplasms / genetics*


  • DNA Transposable Elements
  • DNA, Mitochondrial