GENETICALLY MODIFIED FOODS "All The Difference In The World" By Dennis R. McCalla
A conuniftee examining genetically modified crops for the federal govemment is perpetuating a myth. The Canadian Biotechnology Advisory Committee released its interim report last year and is expected to publish its final report soon. The deadline for comment passed on Jan. 31, but conmittee member Peter Phillips told the pro-biotech AGCare farm group last week that the committee is still accepting submissions. In its interim report, the committee asserts that there is essentially no difference between genetically modified foods and conventional foods. There are, however, several differences. Genetically engineered crops are produced by the forced insertion of genes from unrelated species to give the plant new traits such as resistance to herbicides or insects. They were introduced to Canadian farms vfithout public debate. These genetically modified, or GM, foods are now found in 60 per cent of all processed groceries on superinarket shelves. The federal regulatory agencies. which are part of the same govemment ministries whose mandate is to promote GM foods - have approved these products on the basis of rudimentary tests conducted by industry and have ignored the fact that the consequences of genetic engineering are poorly understood. This approach was roundly criticized in the report of the Royal Society of Canada's expert panel on the future of bood biotechnology commissioned by Ottawa. The report released in January, 2001, explained clearly that GM foods are likely to possess unexpected and potentially harmful properties. Unfortunately, the panel's warning has been ignored by both the government and by the Canadian Biotechnology Advisory Committee in its interim report released last August. These bodies perpetuate the myth that genetic engineering is merely a modern variant of conventional plant breeding and therefore needs no special scrutiny. This stance is convenient for industry since it greatly simplifies the requirements for approval of new GM foods, but leaves consumers and the environment vulnerable to any unexpected hazards these new foods may present. There are, in fact, major differences between genetically engineered foods and those developed by traditional plant breeding - in which genes, from the same or closely related species are introduced into a plant by pollination, with the natural processes of fertilization and genetic recombination doing the rest. These differences include: *Genetic engineering inserts the alien genes randomly into the chromosomes of recipient ceus. Most of the transfon-ned plants that develop are grossly malformed and dysfunctional and are immediately discarded. The few which seem to have the desired characteristics may have undergone subtle but important changes that are not immediately apparent. For example, under conditions of severe drought Roundup Ready soybeans, modified to resist Monsanto's powerful Roundup weed killer, turned out to be less able to convert nitrogen from. the air into usable forms than were non-GM soybeans. * Genes from aniinals and bacteria do not work in plant cells with any degree of efficiency unless they are attached to a powerful "promoter" that tells the alien gene to start working in its new host. This promoter is another segment of DNA, and is generally obtained from a virus. The promoter's role as an �on switch� for the alien gene can also inappropriately switch on unrelated genes that would normally be inactive. * Another unintended effect is gene silencing," in which insertion of an alien gene unexpectedly turns off other genes. For example, insertion of the Bt gene into a strain of potato to make it resistant to the Colorado potato beetle, inexplicably turned off the gene for golden nematode resistance - a totally unrelated trait. This untoward effect was not detected until after approval of the variety. * As Barry Commoner points out in the latest issue of Harper's magazine, the DNA sequence of a single gene may give rise to more than one protein. Humans, for example, produce some 100,000 proteins from only 30,000 to 35,000 genes. Within a normal organism, mechanisms to ensure that genes work together harmoniously have been perfected over many millions of years of evolution. In contrast, introduction of alien genes from unrelated species may produce other unpredictable and potentially hazardous proteins in addition to the one that is sought, Such changes will necessarily go undetected by the simplistic tests now accepted by the regulatory agencies. Industry has claimed that GM foods are the most intensively studied crops ever. Yet, virtually none of the studies they claim to have conducted have been published in the scientific literature where they can be reviewed critically by independent scientists. Even the limited testing which govemment regulators . accept as evidence of safety have been deemed to be confidential business information and excluded from the public eye. The government, then, has ensured that there can be no real independent assessment of the information used to approve GM foods. If GM crops are to remain in commerce, government regulators must: * Acknowledge the unique and unpredictable problems that may be caused by moving genes from one species to another, including unexpected proteins, increases in tonic constituents and changes in the levels of normal constituents, under a variety of growing conditions. * Thoroughly revamp the current, outdated risk assessment protocol, which is based on a discredited understanding of gene function. Integrate new and pivotal information, and require actual testing of nutritional, health and environmental impacts of GM crops. * Drop the secrecy surrounding the approval process which creates the spectre of government-industty collusion. Fully integrate independent scientists , and other concerneds into the process of pre-approval analysis and post-approval monitoring. * Institute a rigorous and independent monitoring process with authority to withdraw fromcomrnerce products shown to be harmful. , Finally, Canada should take seriously the admonition of the editors of the respected British publication Nature Biotechnology, who warned that "the risks of biotechnology are undeniable, and they stem from the unknowable in science. and commerce. It is prudent to recognize and address those risks, not compound them by overly optimistic or foolhardy behaviour." Dennis R. McCalla is a retired vice-president of health sciences at McMaster University. This column is based on his presentation to the Canadian Biotechnology Advisory Committee.
