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Inviting instability: Transposable elements, double-strand breaks, and the maintenance of genome integrity
1Tulane Cancer Center, SL66 and Department of Epidemiology, Tulane University Health Sciences Center, 1430 Tulane Avenue, New Orleans, LA 70112, USA.
Mutation Research
|December 13, 2006
Summary
Mobile elements, or transposable elements (TEs), cause genomic instability in mammals through homology-driven rearrangements. Mammalian DNA repair mechanisms have evolved to mitigate this, but TEs still contribute to genetic diseases.
Area of Science:
- Genomics
- Molecular Biology
- Mammalian Genetics
Background:
- Mobile elements (transposable elements, TEs) are widespread in mammalian genomes.
- Their homologous nature predisposes them to causing genomic rearrangements during recombination and DNA repair.
- TE insertions can lead to deletions, duplications, and large-scale chromosomal changes, posing significant risks.
Purpose of the Study:
- To review the mechanisms of mobile element-induced genetic instability in mammals.
- To highlight the role of TEs in genome integrity challenges and disease.
- To discuss mammalian-specific adaptations in DNA repair.
Main Methods:
- Literature review and synthesis of current knowledge on TE-mediated genomic instability.
- Analysis of mechanisms underlying TE interactions with DNA repair and recombination pathways.
- Examination of evolutionary implications and disease associations.
Main Results:
- TEs contribute significantly to genomic instability via nonallelic homologous recombination and DNA repair errors.
- Over 25 human genetic diseases are linked to TE-mediated rearrangements, including recurrent mutations.
- Mammalian cells possess specialized DNA repair systems to manage interspersed homology from TEs.
- Endonuclease activity of TEs may also drive genomic instability.
Conclusions:
- Mobile elements are a major source of genomic instability and genetic disease in mammals.
- Mammalian DNA repair pathways offer some protection against TE-induced damage.
- Further research is needed to fully elucidate the mechanisms governing TE-mediated instability.
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