The Molecular Basis of Variation Affecting Gene Expression: Evidence from Studies on the Ribosmal RNA Gene Loci of Wheat

  • R. B. Flavell
  • R. Sardana
  • S. Jackson
  • M. O’Dell
Part of the Stadler Genetics Symposia Series book series (SGSS)


A question relevant to an understanding of plant breeding is “What is the molecular basis of allelic variation affecting gene expression?”. The importance of this question is elevated if one accepts the perhaps biased belief that much of the important variation that plant breeders exploit is concerned with variation in the amounts of gene products in time and space during plant development. Many other relevant questions emerge when one wonders about variation in gene expression. For example, does a gene adopt a different structure when it is active compared with when it is silent? How does a plant turn a gene off and on? What kinds of mutations cause a gene to be more or less active.


Cytosine Methylation rDNA Locus Hypersensitive Site CCGG Site Unmethylated Cytosine 
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

© Plenum Press, New York 1990

Authors and Affiliations

  • R. B. Flavell
    • 2
  • R. Sardana
    • 1
  • S. Jackson
    • 1
  • M. O’Dell
    • 1
  1. 1.Cambridge LaboratoryAFRC Institute of Plant Science ResearchTrumpington, CambridgeUK
  2. 2.John Innes Institute and AFRC Institute of Plant Science ResearchNorwich, NorfolkUK

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