Pathways of Genetic Code Evolution in Ancient and Modern Organisms

@article{Sengupta2015PathwaysOG,
  title={Pathways of Genetic Code Evolution in Ancient and Modern Organisms},
  author={Supratim Sengupta and Paul G. Higgs},
  journal={Journal of Molecular Evolution},
  year={2015},
  volume={80},
  pages={229-243}
}
There have been two distinct phases of evolution of the genetic code: an ancient phase—prior to the divergence of the three domains of life, during which the standard genetic code was established—and a modern phase, in which many alternative codes have arisen in specific groups of genomes that differ only slightly from the standard code. Here we discuss the factors that are most important in these two phases, and we argue that these are substantially different. In the modern phase, changes are… 

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