Bulletin of Mathematical Biology

, Volume 67, Issue 6, pp 1355–1368 | Cite as

The impact of including tRNA content on the optimality of the genetic code

  • Hani Goodarzi
  • Hamed Shateri Najafabadi
  • Hamed Ahmadi Nejad
  • Noorossadat Torabi


Statistical and biochemical studies have revealed nonrandom patterns in codon assignments. The canonical genetic code is known to be highly efficient in minimizing the effects of mistranslational errors and point mutations, since it is known that, when an amino acid is converted to another due to error, the biochemical properties of the resulted amino acid are usually very similar to those of the original one. In this study, we have taken into consideration both relative frequencies of amino acids and relative gene copy frequencies of tRNAs in genomic sequences in order to introduce a fitness function which models the mistranslational probabilities more accurately in modern organisms. The relative gene copy frequencies of tRNAs are used as estimates of the tRNA content. We also altered the rule previously used for the calculation of the probabilities of single base mutation occurrences. Our model signifies higher optimality of the genetic code towards load minimization and suggests the presence of a coevolution of tRNA frequency and the genetic code.


Codon Mathematical Biology Codon Usage Genetic Code Codon Position 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Society for Mathematical Biology 2005

Authors and Affiliations

  • Hani Goodarzi
    • 1
  • Hamed Shateri Najafabadi
    • 1
  • Hamed Ahmadi Nejad
    • 2
  • Noorossadat Torabi
    • 1
  1. 1.Department of Biotechnology, Faculty of ScienceUniversity of TehranTehranIran
  2. 2.Department of Computer EngineeringSharif University of TechnologyTehranIran

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