Genome scrambling – myth or reality? Transformation-induced mutations in transgenic crop plants

Journal or Publishing Institution: EcoNexus

Study: http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.663.1981&rep=rep1&type=pdf

Author(s): Wilson, A., Latham, J. and Steinbrecher, R.

Article Type: Report

Record ID: 1247

Summary: Internationally, safety regulations of transgenic (genetically modified or GM) crop plants focus primarily on the potential hazards of specific transgenes and their products (e.g. allergenicity of the B. thuringiensis cry3A protein). This emphasis on the transgene and its product is a feature of the case-by-case approach to risk assessment. The case-by-case approach effectively assumes that plant transformation methods (the techniques used to introduce recombinant DNA into a plant) carry no inherent risk. Nevertheless, current crop plant transformation methods typically require tissue culture (i.e. regeneration of an intact plant from a single cell that has been treated with hormones and antibiotics and forced to undergo abnormal developmental changes) and either infection with a pathogenic organism (A. tumefaciens) or bombardment with tungsten particles. It would therefore not be surprising if plant transformation resulted in significant genetic consequences which were unrelated to the nature of the specific transgene. Indeed, both tissue culture and transgene insertion have been used as mutagenic agents (Jain 2001, Krysan et al. 1999).

In this report we examine the mutations introduced into transgenic crop plants by plant transformation. We have searched and analysed the relevant scientific literature for Agrobacterium-mediated transformation and particle bombardment, the two most frequently used plant transformation methods. We have also analysed the molecular data submitted to the USDA in applications requesting commercial approval for transgenic cultivars. Lastly, we have examined whether mutations arising from plant transformation have the potential to be hazardous and whether current safety tests are robust enough to detect hazardous mutations before they reach the market.

Citation: Wilson, A., Latham, J. and Steinbrecher, R., 2004. Genome Scrambling-Myth Or Reality?: Transformation-induced Mutations in Transgenic Crop Plants: Technical Report-October 2004. EcoNexus.