Meeting on the “Genetic Basis of Unintended Effects in Modified Plants”

  • Start Date/Time :
  • End Date/Time :
  • Location : Ottawa, Ontario, Canada
  • Venue : Lord Elgin Hotel


  • Canadian Food Inspection Agency (CFIA)
  • HESI Protein Allergenicity Technical Committee (PATC)
  • ILSI International Food Biotechnology Committee (IFBiC)
  • ILSI Research Foundation
  • CropLife International


Meeting Materials

Background and Objectives

As transgenic (GM) products worthy of commercialization became available, procedures were instituted to ensure that these plants were as safe for food, feed, and environmental release as their conventional counterparts. These procedures addressed the two types of changes that could be considered in a GM food / feed / environmental release safety assessment.

Of these two possible types of changes, one is referred to as “intended.” This type of change in a new product is brought about by the introduced transgene. Because many transgenes express a known and characterized protein, procedures can be developed that directly assess the protein for toxicity and allergenicity, as well as measure levels of metabolites that may be associated with the protein’s function.

The other type of change is referred to as “unintended.” This potential change could materialize as a consequence of gene insertion or from random mutations that take place during the transformation and tissue culture process. Because the nature of unintended changes is unknown, there is no direct test for them. However, the potential for an unintended change to present a food or feed hazard is currently assessed through compositional analyses and agronomic studies. Some regulatory authorities may also require animal feeding tests.

Thus far, no adverse unintended changes have materialized. Consequently, a reevaluation of the original premise is merited.

The objectives of this meeting are to explore current knowledge and data gaps on unintended effects and discuss how this information can inform and improve risk assessments. The meeting will feature presentations on the molecular basis for unintended changes, a hypothesis-driven look at unintended effects in conventional and GM crops, and the consequences of unintended effects from a safety assessment perspective. Finally, a panel of experts will discuss the extent to which unintended or unexpected changes are hazardous.


Unintended effects in genetically engineered plants: what they are and how they are assessed in Canada
Mr. Phil Macdonald, Canadian Food Inspection Agency

The molecular basis for unintended changes in plants

The molecular biology of gene functions
Dr. Mark Jordan, Agriculture and Agri-Food Canada

The molecular biology of plant genomic changes
Prof. Wayne Parrott, University of Georgia, US

What does it take to bring an ag biotech seed product to market?
Dr. Laura Privalle, Bayer CropScience, US

The roles of backcrossing and other breeding strategies in removing unintended effects caused by the transformation process
Dr. Phil Bregitzer, U.S. Department of Agriculture - Agricultural Research Service

How much of a hazardous substance would have to be produced before it poses a risk?
Prof. Andrew Bartholomaeus, University of Canberra, University of Queensland, Australia Video


Dr. Greg Ladics, DuPont Pioneer

Hypothesis-driven survey of unintended changes: observed incidences of unintended effects

The biology of naturally occurring insertions
Dr. Justin Vaughn, University of Georgia, US

Unintended effects on allergens in carrots and apples
Dr. Thomas Holzhauser, Paul-Ehrlich-Institut, Germany

Hypothesis-driven survey of unintended changes: GM crop case studies

Single gene traits
Dr. Alan Raybould, Syngenta, UK

Hypothesis-driven evaluations of drought-tolerant corn in safety assessments
Dr. Elena Rice, Monsanto, US

Quality traits: altered starch composition in potato
Dr. Christine Wandelt, BASF, Germany

Hypothesis-driven survey of unintended changes: food/feed safety

Identification/assessment of possible unintended effect(s) on the overall allergenicity of GM plants
Prof. Jean-Michel Wal, AgroParisTech, France

Towards rational assessment of changes in small molecules by leveraging genomics and metabolic network modeling
Dr. Sue Rhee, Carnegie Institution for Science, US

Food and feed safety of new plant varieties: how to assess unintended changes?
Dr. Esther Kok, RIKILT Wageningen UR, Netherlands

Hypothesis-driven survey of unintended changes: environmental

Problem formulation
Prof. Alan Gray, Centre for Ecology and Hydrology, UK

Can unintended effects lead to increased weediness/invasiveness?
Dr. Paul Keese, Office of the Gene Technology Regulator, Australian Government

Studying unintended effects confuses the nontarget risk assessment
Dr. Jörg Romeis, Agroscope, Institute for Sustainability Sciences ISS, Switzerland


Kessler DA, Taylor MR, Maryanski JH, Flamm EL, Kahl LS. 1992. The safety of foods developed by biotechnology. Science 256: 1747-1749. Link

NRC. 2004. Safety of Genetically Engineered Foods: Approaches to Assessing Unintended Health Effects. Chapter 3. Unintended Effects from Breeding, pp 39-71. Committee on Identifying and Assessing Unintended Effects of Genetically Engineered Foods on Human Health, National Research Council. National Academies Press, Washington, DC. Link

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