Selection on codon bias.

  title={Selection on codon bias.},
  author={Ruth Hershberg and Dmitri A. Petrov},
  journal={Annual review of genetics},
In a wide variety of organisms, synonymous codons are used with different frequencies, a phenomenon known as codon bias. Population genetic studies have shown that synonymous sites are under weak selection and that codon bias is maintained by a balance between selection, mutation, and genetic drift. It appears that the major cause for selection on codon bias is that certain preferred codons are translated more accurately and/or efficiently. However, additional and sometimes maybe even… 

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