Confounded cytosine! Tinkering and the evolution of DNA

Nat Rev Mol Cell Biol. 2001 Feb;2(2):147-51. doi: 10.1038/35052091.


Early in the history of DNA, thymine replaced uracil, thus solving a short-term problem for storing genetic information--mutation of cytosine to uracil through deamination. Any engineer would have replaced cytosine, but evolution is a tinkerer not an engineer. By keeping cytosine and replacing uracil the problem was never eliminated, returning once again with the advent of DNA methylation.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Cytosine / metabolism*
  • DNA / genetics*
  • Evolution, Molecular*


  • Cytosine
  • DNA