On the Evolution of the Standard Genetic Code: Vestiges of Critical Scale Invariance from the RNA World in Current Prokaryote Genomes
2009

Evolution of the Standard Genetic Code from the RNA World

Sample size: 7 publication Evidence: moderate

Author Information

Author(s): José Marco V., Govezensky Tzipe, García José A., Bobadilla Juan R.

Primary Institution: Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México

Hypothesis

The study investigates whether current prokaryote genomes retain vestiges of the primeval RNA World and how the standard genetic code evolved from it.

Conclusion

Most current prokaryotes may still contain relics of the primeval RNA World, and two extended RNA codes represent plausible evolutionary paths to the standard genetic code.

Supporting Evidence

  • The scaling properties of some codons from the RNA code and most codons from both extended RNA codes were found to be identical or very close to those of the standard genetic code.
  • Computer simulations showed that random mutations over three billion years were insufficient to destroy the observed patterns.
  • The study derived two genetic codes from which the primeval RNA code could have originated the standard genetic code.

Takeaway

Scientists looked at tiny parts of DNA from different bacteria to see if they still show signs of an ancient RNA code, and they found that many do.

Methodology

The study used genomes of four Eubacteria and three Archaeas, applying a renormalization group approach to analyze scaling properties of triplet sequences.

Limitations

The study may not account for all possible variations in genetic codes across different organisms.

Participant Demographics

The study analyzed genomes from four Eubacteria and three Archaeas.

Digital Object Identifier (DOI)

10.1371/journal.pone.0004340

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