Establishing Substantial Equivalence: Transcriptomics

  • María Marcela Baudo*
  • Stephen J. Powers
  • Rowan A. C. Mitchell
  • Peter R. Shewry
Part of the Methods in Molecular Biology™ book series (MIMB, volume 478)


Regulatory authorities in Western Europe require transgenic crops to be substantially equivalent to conventionally bred forms if they are to be approved for commercial production. One way to establish substantial equivalence is to compare the transcript profiles of developing grain and other tissues of transgenic and conventionally bred lines, in order to identify any unintended effects of the transformation process. We present detailed protocols for transcriptomic comparisons of developing wheat grain and leaf material, and illustrate their use by reference to our own studies of lines transformed to express additional gluten protein genes controlled by their own endosperm-specific promoters. The results show that the transgenes present in these lines (which included those encoding marker genes) did not have any significant unpredicted effects on the expression of endogenous genes and that the transgenic plants were therefore substantially equivalent to the corresponding parental lines.

Key Words:

Bread wheat transgenics transcriptomics transgene expression substantial equivalence gluten proteins 



Rothamsted Research receives grant-aided support from the Biotechnology and Biological Sciences Research Council of the UK. The transcriptomic studies were supported by a grant under the BBSRC, Gene Flow Initiative (ref. GM 14152). The authors would like to thank Mr. Adrian Price at Rothamsted Research for discussions of methods for microarray data analysis. We also acknowledge our colleagues Prof. Michael Holdsworth (University of Nottingham), Prof. Keith Edwards (University of Bristol), Ms. Rebecca Lyons, and Dr. Gabriela M. Pastori (Rothamsted Research).


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Copyright information

© Humana Press, a part of Springer Science+Business Media, LLC 2009

Authors and Affiliations

  • María Marcela Baudo*
    • 1
  • Stephen J. Powers
    • 2
  • Rowan A. C. Mitchell
    • 1
  • Peter R. Shewry
    • 1
  1. 1.Centre for Crop Genetic Improvement, Department of Plant SciencesRothamsted ResearchHarpenden, HertfordshireUK
  2. 2.Centre for Mathematical and Computational Biology, Department of Biomathematics and BioinformaticsRothamsted ResearchHarpenden, HertfordshireUK

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