Standard Article

Codon Usage

  1. Etsuko N Moriyama

Published Online: 15 JUL 2006

DOI: 10.1038/npg.els.0005102



How to Cite

Moriyama, E. N. 2006. Codon Usage. eLS. .

Author Information

  1. University of Nebraska, Lincoln, Nebraska, USA

Publication History

  1. Published Online: 15 JUL 2006


Genetic codes have degeneracy; that is, most amino acids (18 out of 20 in the universal genetic code) are encoded by more than one codon. Codons encoding the same amino acid are called synonymous codons. In both prokaryotic and eukaryotic genes, the synonymous codons are not used with equal frequencies.


  • synonymous codon;
  • translational selection;
  • mutation bias;
  • tRNA abundance;
  • gene expression