Journal of Molecular Evolution

, Volume 42, Issue 5, pp 597–601 | Cite as

On malleability in the genetic code

  • Dennis W. Schultz
  • Michael Yarus
Letter to the Editor


To explain now-numerous cases of codon reassignment (departure from the “universal” code), we suggest a pathway in which the transformed codon is temporarily ambiguous. All the unusual tRNA activities required have been demonstrated. In addition, the repetitive use of certain reassignments, the phylogenetic distribution of reassignments, and the properties of present-day reassigned tRNAs are each consistent with evolution of the code via an ambiguous translational intermediate.


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Copyright information

© Springer-Verlag New York Inc 1996

Authors and Affiliations

  • Dennis W. Schultz
    • 1
  • Michael Yarus
    • 2
  1. 1.Department of Molecular and Medical GeneticsOregon Health Sciences UniversityPortlandUSA
  2. 2.Department of Molecular, Cellular, and Developmental BiologyUniversity of ColoradoBoulderUSA

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