An Overview of the Introns-First Theory

@article{Penny2009AnOO,
  title={An Overview of the Introns-First Theory},
  author={David Penny and Marc P. Hoeppner and Anthony M. Poole and Daniel C. Jeffares},
  journal={Journal of Molecular Evolution},
  year={2009},
  volume={69},
  pages={527-540}
}
We review the introns-first hypothesis a decade after it was first proposed. It is that exons emerged from non-coding regions interspersed between RNA genes in an early RNA world, and is a subcomponent of a more general ‘RNA-continuity’ hypothesis. The latter is that some RNA-based systems, especially in RNA processing, are ‘relics’ that can be traced back either to the RNA world that preceded both DNA and encoded protein synthesis or to the later ribonucleoprotein (RNP) world (before DNA took… 
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42 Citations
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42 Citations

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These aspects were addressed to add to the understanding of mechanisms that control the fate of introns and could be instrumental in regulating genomic output and hence cell fate.
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Intron creation and DNA repair
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Findings in support of the DNA repair hypothesis that provides a global mechanistic scenario for intron creation are reviewed, which posit that DNA repair processes are a major source of intron formation.
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TLDR
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