April 2001
The Science and Non-Science of Genetically-Modified Food
by Peter McCourt
In the 1960s, a team of plant breeders led by Norman Borlaug introduced a collection of crop varieties and hybrids that had been bred for increased quality and yield. These crops successfully maintained the safety of the food supply for the growing world population and for this reason Dr. Borlaug was awarded the Nobel Prize for Peace in 1970. Although this "Green Revolution" helped to feed the 2.3 billion new mouths that have been added to the world population in the intervening 40 years, the battle for food security is far from won. Improvements in crop yields using Green Revolution breeding technologies have plateaued, yet by the year 2040, another 3.6 billion people will be added to the world population. To feed an additional 80 million people each year is not only a daunting task for the agricultural community, but has serious repercussions for the planet's ecosystem. Furthermore, even if Green Revolution technologies could identify new opportunities to improve yield and crop hardiness, the introduction of these traits requires hundreds of acres of farmland, thousands of researchers, and decades of trials to produce significant improvement, and we do not have the time. Fortunately, with the advent of plant biotechnology, it is now possible to circumvent many of the resource problems inherent in traditional breeding methods.
The effects of these technologies to make genetically-modified (GM) crops throughout the world are striking. In 1986, there were fewer than 10 field-tested GM crop experiments; in 1992, the number rose to 400, and has virtually doubled each year since 1988. To date, over 30 different crop species have been genetically modified and Canada now grows more than 33 million acres of GM crops representing 10 percent of the world's supply. The first-generation GM crops focused on increasing production and lowering production costs. In the mid-1990s the cultivation of virus-, insect-, and herbicide-resistant GM crops accounted for 5 to 10 percent increases in yield and a saving of up to 40 percent on herbicides and insecticides (James, 1998). However, this is only the beginning. Plant researchers are sequencing the DNA of entire genomes to gain the ability to manipulate metabolic pathways and improve numerous agronomic traits. The spectacular yield increases seen so far and the further potential of these technologies would make you think that there would be an enthusiastic acceptance of GM crops in both the developed and developing worlds. On the contrary, however, this technology has led to consumer boycotts of GM foods, anxious multinational corporations declaring their products are not genetically modified and, in severe cases, to the destruction of GM crops in the name of stopping the "genetic pollution" of our ecosystems. Many countries, and in particular Europe, have restricted imports and the release of GM crops. Most of this anti-scientific fervour comes from environmental extremists based in rich developed nations, or from the privileged few of the developing world. Why are these special interest groups so concerned? Millions of people now and in the future could benefit from GM technology.
Like many important issues, competing groups have their own agendas and often the considerations are based on good sound bites rather than on good science. Unfortunately, the truth is seldom plain, and never simple; this is also true in the GM food debate. The arguments against the genetic modification of our food supply fall into four main categories, listed below.
Ethical arguments
Transferring genes between organisms in a laboratory is not natural and is therefore unethical.
This argument ignores the fact that humanity has manipulated the evolution of organisms since plant and animal breeding came into existence. Even nature does it. For example, the wheat varieties that now feed much of the world are the result of a natural hybridization of three wheat species that were indigenous to the Middle East. Modern corn is considered to be the hybridization of two different species. One only has to look at fossilized corncobs that are one-tenth the size of modern day cobs to see how a combination of nature and human intervention has changed this crop. Although this historical perspective muddies what is natural and what is not, detractors counter with the argument that methods used by plant geneticists to introduce genes into plants are unnatural, particularly when the genes being introduced are from different species. On this point, however, the "unnatural moving" of genes between species is also found in nature. To be exact, nature moves genes between species so well that plant scientists piggyback on these natural systems to move genes of interest into crops.
Safety argument
Releasing GM crops will have unforeseen consequences on our health. Thus, any new crop which is genetically modified needs to be treated differently and put through a battery of special tests.
The argument is that the insertion of genes often combined with novel DNA sequences that regulate their expression in the plant could result in unpredictable effects. Although this could be true, it is just as likely to occur in nature or by any other traditional breeding process. The food we eat has been continuously genetically engineered by natural phenomena in ways that do not differ from the way we carry out GM technology now. For example, up to 20 percent of some plant genomes contain genetic elements that destabilize genes and genomes, move genes around, mutate and rearrange themselves randomly. Furthermore, the hybridization of genomes of various species that occurs in traditional breeding programs also leads to new and untested combinations of genes. The mistake of the safety argument is that the problem is the process of crop production. The concern should be on the product—not how it was made. No food product, whether traditional or modified by recombinant DNA, is without risk; this is why government agencies test these products. It is ironic, however, that many products found on the shelves of health food stores are not subjected to the same regulatory testing. Based on the non-scientific belief that nature is benevolent, health food addicts may be surprised to find that many plants naturally produce toxic compounds so that animals like ourselves will not eat them.
Ecological arguments
Many opponents of GM crops say we must return to an ecologically-based view of the world. If we continue with high-input agriculture that requires pesticides, herbicides, and fertilizers we will destroy the earth. Furthermore, these new GM varieties will "genetically pollute" the natural world and wreck havoc on our ecosystem.
However, we must feed 5 billion people now, and nearly 9 billion in the future. Biotechnology can help, and there is no reason to believe this technology cannot be used to allow resources to be used more wisely. For example, today, 600 million hectares of wheat are grown worldwide. If we were to limit ourselves to the same wheat strains that were available in 1965, we would need an additional 850 million hectares of land to grow the same amount of wheat (Borlaug, 2000). Even if the land were available, the costs in soil erosion and lost ecosystems would be devastating. For example, despite the fact that tropical forests are unique ecosystems, approximately 11 million hectares are cleared every year by farmers searching for more productive land. Better yielding GM crop varieties could slow this pace, which is certainly a better alternative ecologically to the conversion of forests into agricultural land. The anti-GM groups, however, counter that the advantages of GM plants do not address the concern of "genetic pollution" of natural populations. "Genetic pollution" is defined by environmentalists as the continuous mixing of foreign genes into the ecosystem. In the case of GM crops, however, we are talking about only a few new genes entering the ecosystem, and there is no scientific evidence that these genes confer a selective advantage to plants outside the farmer's fields. Moreover, even if genes did move from the farmer's field into nature, these events are minuscule compared to the non-GM genetic pollution that is presently occurring.
Take, for example, the thousands of alien genes that gardeners in Canada introduce into the ecosystem every year. In the United Kingdom alone, gardeners have introduced approximately 3,000 foreign species into the country, and as many as 60 of these have hybridized with indigenous species (Trewavas, 1999). Many of these species are resistant to all known herbicides. However, you do not see environmental zealots slashing and burning English gardens in the name of "genetic pollution" with the same fervour that they have for canola fields.
Anti-corporate arguments
Corporations are out to make money and will not look out for human welfare. We cannot rely on them.
This may be true. However, corporations are also in the business of making products that will sell. If we believe they are the evil empire, then we should ban cars, entertainment, and computers, since corporations also make these products. There is no reason to believe that biotechnology corporations are any more evil than any other corporations. I believe a more serious corporate concern is not that we will be flooded with GM technology, but that GM technology will be unavailable to the developing world. The importance of agriculture to companies comes from economic value as decided by the developed nations, particularity the United States and Western Europe. Most government and corporate research groups are not interested in tropical and subtropical agriculture. It would be distressing if people in the developing world had limited access to GM technology as they are the ones who could most benefit from these products.
Although we have much to thank the environmental movement for over the past 40 years, I find the pseudo-science promoted by bandwagon environmentalists concerning GM foods to be disturbing. In the former Soviet Union a pseudo-scientist, T.M. Lysenko, who did not believe in genetics and touted the Communist party line, was placed in charge of plant breeding for the country. His bizarre ideas and non-scientific opinions were one of the major reasons for the continued failure of Soviet agriculture, which in turn contributed to the collapse of the USSR. Hopefully, the religious zeal of the anti-science environmentalists will not lead us all down a similar path.
References
Borlaug, N.E. (2000). "Ending World Hunger. The Promise of Biotechnology and the Threat of Antiscience Zealotry." Plant Physiology 124, pp. 487-490.
James, C. (1998). "Update in the Development and Commercialization of Genetically Modified Crops." Int. Serv. Acquisition Agrobiotechnol. Appl. Briefs 5, pp. 1-20.
Trewavas, A. (1999). "Much Food, Many Problems." Nature. Vol. 402, pp. 231-232.
Peter McCourt is a professor in the Botany Department at the University of Toronto and holds an NSERC Chair in Plant Genetics.
info@fraserinstitute.ca
4th Floor, 1770 Burrard Street, Vancouver, BC, Canada, V6J 3G7
Tel: (604) 688-0221 Fax: (604) 688-8539 Book Orders: 1-800-665-3558 ext. 580
You can contact us at the above email address for any comments or information requests. Please report any dead links or technical problems.