Standard Article

Orthologues, Paralogues and Xenologues in Human and Other Genomes

  1. Olga Zhaxybayeva1,
  2. J Peter Gogarten2,
  3. Lorraine Olendzenski3

Published Online: 14 MAR 2008

DOI: 10.1002/9780470015902.a0005298.pub2



How to Cite

Zhaxybayeva, O., Gogarten, J. P. and Olendzenski, L. 2008. Orthologues, Paralogues and Xenologues in Human and Other Genomes. eLS. .

Author Information

  1. 1

    Dalhousie University, Halifax, Nova Scotia, Canada

  2. 2

    University of Connecticut, Storrs, Connecticut, USA

  3. 3

    St. Lawrence University, Canton, New York, USA

Publication History

  1. Published Online: 14 MAR 2008

This is not the most recent version of the article. View current version (15 MAR 2013)


Homologous genes share a common evolutionary ancestor and can be orthologues (derived from speciation events), paralogues (derived from gene duplication events) or xenologues (derived from horizontal transfer or lineage fusion). Comparative analysis of the human genome indicates high levels of recent and ancient duplication at the level of nucleotides, genes and chromosome segments, and no unambiguous examples of recent transfer from bacteria.


  • gene duplication;
  • homology;
  • orthology;
  • paralogy;
  • xenology