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Base Pairing in DNA: Unusual Patterns

  1. William H Gmeiner1,
  2. Bernhard J Walberer2

Published Online: 19 APR 2001

DOI: 10.1038/npg.els.0003127



How to Cite

Gmeiner, W. H. and Walberer, B. J. 2001. Base Pairing in DNA: Unusual Patterns. eLS. .

Author Information

  1. 1

    Wake Forest University, Winston-Salem, North Carolina, USA

  2. 2

    University of California at San Francisco, San Francisco, California, USA

Publication History

  1. Published Online: 19 APR 2001


Watson–Crick base pairs comprise just two of 44 reasonable base pairing geometries involving the four common deoxyribonucleotides (dA, dC, dG, dT) in either their neutral or protonated forms. Most of the 42 non-Watson–Crick base pairs have been observed experimentally in DNA. Although these unusual base pairs are difficult to detect in vivo, unusual base pairing may be significant for the biological functions of DNA.


  • mutation;
  • transversion;
  • transition;
  • telomere;
  • I-motif;
  • Hoogsteen