Comparative Analysis of Gene Conversion Between Duplicated Regions in Brassica rapa and B. oleracea Genomes

  • Jinpeng Wang
  • Hui Guo
  • Dianchuan Jin
  • Xiyin WangEmail author
  • Andrew H. PatersonEmail author
Part of the Compendium of Plant Genomes book series (CPG)


Plant genomes contain many duplicated genes, some of which were produced by recursive polyploidizations. These duplicated genes may evolve interactively and even concertedly through homoeologous recombination. Here, we explored likely gene conversion in Brassica rapa and Brassica oleracea. By checking gene colinearity, we detected 4296 duplicated genes existing in both the species, which were produced by whole-genome triplication from their common ancestor. Incongruities of homologous gene tree topologies indicated that 8 % of these duplicated genes were converted by one another after the divergence of B. rapa and B. oleracea. These converted genes are more often from larger duplicated chromosomal blocks, indicating that illegitimate recombination is more likely to occur between larger homoeologous chromosomal regions. This research contributed to understanding genome stability and gene evolution after polyploidization.


Gene Conversion Duplicate Gene Brassica Species Illegitimate Recombination Homoeologous Recombination 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2015

Authors and Affiliations

  1. 1.Center for Genomics and Computational BiologyNorth China University of Science of TechnologyTangshanChina
  2. 2.College of Life SciencesNorth China University of Science and TechnologyTangshanChina
  3. 3.Plant Genome Mapping LaboratoryUniversity of GeorgiaAthensUSA
  4. 4.Department of Plant BiologyUniversity of GeorgiaAthensUSA
  5. 5.College of SciencesNorth China University of Science and TechnologyTangshanChina
  6. 6.Institute of BioinformaticsUniversity of GeorgiaAthensUSA
  7. 7.Department of Crop and Soil ScienceUniversity of GeorgiaAthensUSA
  8. 8.Department of GeneticsUniversity of GeorgiaAthensUSA

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