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Threats of unintended gene transfers

Engineered genes may offer vast potential improvements, but they are also more mobile than scientists had suspected. Viral genes used to modify crops can be transferred to infecting viruses (Greene and Allison, 1994). Genes inserted in crop plants by genetic engineering can be transferred rapidly to wild weedy relatives, even over considerable distances, and thus escape from control (Mikkelsen et al., 1996; Timmons et al., 1995). Similar concerns have been expressed about genetically altered animals such as 'super salmon' (MacKenzie, D., 1996). There have been concerns for potential environmental or health disasters caused by genetically modified organisms (Independent Panel on Sustainable Development, 1996). Extra care will thus be required in planning genetic alterations and releasing the resulting organisms. In response to these concerns, government-designated experts adopted the UNEP International Technical Guidelines for Safety in Biotechnology in December 1995.

Biotechnology can also have economic and social impacts. The use of genetically modified temperate crops such as rapeseed in developed countries to replace tropical crop products such as coconut and palm oils could eventually threaten the exports and thus the economies of poor developing countries (Kleiner, 1995a).


Greene, Ann E., and Richard F. Allison. 1994. "Recombination between viral-RNA and transgenic plant transcripts." Science 263:1423-1425.

Independent Panel on Sustainable Development (UK). 1996. Report quoted in "The fifth horseman." New Scientist, 27 January 1996, p. 11.

Kleiner, Kurt. 1995a. "Altered crop threatens poor nations." New Scientist, 17 June 1995, p. 10.

MacKenzie, Debora. 1996. "Can we make supersalmon safe?" New Scientist, 27 January 1996, p. 14-15.

Mikkelsen, Thomas R., Bente Andersen and Rikke Bagger Jorgensen. 1996. "The risk of crop transgene spread." Nature 380:31. 7 March 1996.

Timmons, Aileen, Eileen O'Brien, Yvonne Charters and Mike Wilkinson. 1995. (Scottish Crop Research Institute) Quoted in Coghlan, Andy. "Far-flung pollen raises spectre of superweed." New Scientist, 11 November 1995, p. 10.


Emerging Issues

Threats of unintended gene transfers

UNEP/DEWA/Earthwatch 1996-2003