Standard Article

rRNA Genes: Evolution

  1. Iris L Gonzalez1,
  2. James E Sylvester2

Published Online: 21 DEC 2007

DOI: 10.1002/9780470015902.a0006131.pub2



How to Cite

Gonzalez, I. L. and Sylvester, J. E. 2007. rRNA Genes: Evolution. eLS. .

Author Information

  1. 1

    AI duPont Hospital for Children, Wilmington, Delaware, USA

  2. 2

    Nemours Children's Clinic, Jacksonville, Florida, USA

Publication History

  1. Published Online: 21 DEC 2007


The large ribosomal ribonucleic acid (rRNA) gene arrays undergo concerted evolution on both homologous and nonhomologous chromosomes, but coding and noncoding parts of the ribosomal deoxyribonucleic acid (rDNA) unit are not homogenized to the same extent and at the same rate. We do not know if this is due to selection pressure, to localized recombination or gene conversions. New findings regarding array organization have raised the possibility that there are isolated clusters that only homogenize among/within themselves. It is not known if these noncanonical clusters are functional or not.


  • rRNA;
  • rDNA;
  • ribosome;
  • acrocentric;
  • evolution