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Biotechnology and Society---Part
21
GM crops - boon or bane?
It is difficult to argue with a belly since it has no ears. - Cato the Elder, statesman (234-139 BCE)
 We described in the previous article how food crops and cash crops are being genetically modified to produce more nutritious, pest-tolerant and high-yielding crops. When such genetic manipulation of crops yields benefits to mankind one would expect that the public would welcome it with open arms. Right? Not quite.
We described several benefits arising from genetically modified (GM) crops. However, no technology is without risks and the benefits have to be weighed against the risks. Since one does not know the long-term effects of gene modification, caution is advised in proceeding with genetic modification of crops. Consider the following situations.
Monarch butterflies: The monarch butterfly was in the news three years ago. Bt corn (the corn genetically modified to resist the damaging effect of the corn borer pest) was considered harmful to the monarch
butterfly. It is very common that the milkweed plant grown along the peripheries of cornfields is a natural food for the larvae of the monarch butterfly. Research indicated that the monarch butterfly larvae when fed on milkweeds sprayed with the Bt
pesticide protein did not grow up to the flight stage. Environmentalists immediately jumped on the biotech industry with criticism that pollen from Bt corn could kill the larvae of monarch butterflies.
A workshop organised by the US Department of Agriculture (USDA) encouraged scientists from several institutions to conduct an extensive study. The conclusion of the studies bore out the general safety of the transgenic corn with a rare exception of a single variety which produced large amounts of Bt protein in the pollen. The biotech industry also countered by saying that more butterflies are killed in the highway by hitting trucks than those that will be harmed by the milkweeds contaminated by corn pollen containing Bt. The controversy died down in recent times after more research indicated that it is not as serious a problem as it was made out to be. Still it is a thorny issue.
 Prodigene: Recently, there were a couple of incidents involving mishaps with GM
plants. A biopharmaceutical company, Prodigene Inc, was fined by the USDA for allowing corn that was genetically engineered to produce a pig vaccine to contaminate 500,000 bushels of soybeans in Nebraska. It was just an oversight that some stray corn seeds got left out in the field in which it was grown, germinated in the field and got harvested together with soybeans planted in the same field the next season. The soybeans had to be destroyed as a precaution. In all likelihood there would not have been any problem, but in the absence of evidence otherwise, it is advisable to be safe than sorry.
Starlink: In addition there was another episode with Starlink corn which was also genetically modified but not approved for human consumption. It so happened that one shipment of such corn got into the human food chain through a fast food outlet. While such a small contamination would not have caused any damage to the health of the human population, the very idea of such contamination possibilities raise red flags throughout the industry and consumer action groups.
When Monsanto developed the Roundup Ready corn which can resist the effects of the herbicide when they are in full growth thereby enabling the application of the herbicide at a late stage of the crop growth, critics took the company to task for promoting excessive use of their own herbicide, which was considered environmentally irresponsible and economically gouging the farmers and ultimately the consumers.
 Food and drugs: A tussle is also evident between the US
food and biotechnology industries over plans to genetically modify
food crops to make drugs and chemicals.
Bio-pharming is seen as the next wave for the crop-biotechnology sector to make life-saving drugs inexpensively. But politically powerful trade groups for the $ 500 billion food sector are gearing up to lobby federal regulators for tougher rules for the bio-pharming companies so that the food industry will not be blamed for any eventual mishap in the crop biotechnology sector. The USDA requires bio-pharming companies to keep their experimental crops a certain distance from fields of related plants and to time the reproductive cycle of their fields so that they are out of synch with those of the food crops in the neighbouring fields to prevent any cross-pollination.
 To keep pharmaceutical corn from cross-pollinating with corn used for food or feed, the USDA requires two methods of separation.
1. No other corn plants are grown within a radius of 0.5 mile of the transgenic test plants.
2. The pharmaceutical corn must be planted no fewer than 21 days before or after any other corn planted at a distance of 0.5 to 1.0 mile from the test plants.
Scientific community: In addition to the protests carried out by environmental groups, even the scientific community is advising extreme caution in proceeding with bio-pharming. If the transgene (foreign gene put in the plant) moves into the wild relatives of the
crop there could be a spread of the pharmaceutical substance that could have an impact on wildlife and microbial populations, not unlike the antibiotic resistance seen among bacterial populations.
Swiss researchers have shown that green lacewings, a group of beneficial predatory insects, suffered a higher death rate and delayed development when fed European corn borers which had eaten Bt corn compared with lacewings fed borers given non-Bt corn.
The scientific community is also concerned about cross-contamination in food crops in the developing world when the transgenic-contaminated seeds are used. The National Research Council (an independent policy arm of the Federal government) concluded: “It is possible that crops transformed to produce pharmaceutical and other industrial compounds might mate with plantations grown for human consumption, with the unanticipated result of novel chemicals in the human food supply.” One possible solution would be to confer sterility on the transgenic crop which would render them unsuitable to breed with conventional crops which would address many of the concerns about gene flow outside the transgenic crop.
 Friends of the Earth (FOE): This group completed a study on current field trials of crops bioengineered to produce pharmaceutical proteins in plants such as
corn, soybeans,
tobacco and rice. FOE is apprehensive that despite the rules to safeguard against contamination, accidents might happen which are unimaginable right now. FOE claims a much safer route to make drugs from plants would be plant cell cultures and secretion of biopharm proteins from plant roots into hydroponic media. However, this is neither desirable nor economically viable for the biopharmaceutical companies intending to use plants for producing therapeutic drugs through food crops.
International impact: There is also an ongoing struggle between the US, which generally supports GM crops, and the European Union which does not. Certain States in the European Union have vehemently opposed the approval of transgenic crops and a moratorium on the importation of corn shipments from the US is in effect. US food processors are angry that science and politics are getting mixed up and affect their well-being and worldwide economics. European farmers who grow conventional crops are the force behind the moratorium. The US has complained to the World Trade Organization (WTO) alleging that the de facto moratorium is an unfair trade barrier which violates WTO rules. Now the European parliament is taking a different approach by asking for labelling of the GM crops and traceability of the GM crops so that no mixing occurs between conventional and GM crops.
Before GM products can be accepted in Europe, public opinion has to change or the GM food should be considered to deliver an extraordinary benefit, either health-wise or economic.
Conclusions:
 1. The US experience with GM crops, while extensive, does not justify complacency about potential risks. Only two traits, herbicide resistance and insect resistance, have been commercial successes. Crops with other traits have failed to achieve economic benefits or did not fulfil the R & D goals.
2. The US government provides very little post-market oversight of the biotech foods although the regulatory elements function well before and during approval of the GM crops. The weak monitoring and enforcement systems of the government amounting to “don’t look, don’t find” mentality is not very helpful in detecting significant violations.
3. The scientific overtones concerning risk assessment and risk management spell not a comfortable situation due to serious underfunding of research in this area. Many features of GM crops, for example, impact of stacked genes, and unresolved issues about Bt allerginicity raise concerns that have not been carefully investigated.
4. The diversity promised in future products and the issues they are likely to raise are expected to severely strain the current regulatory system, especially with respect to oversight.
5. Finally, scientific evidence gathered to date, while encouraging, does not support the conclusion that GM crops are intrinsically safe for human health or for the environment at large. The future products of the biotech industry with respect to GM crops are so loaded with ambitious goals which would boggle the mind. It would be unwise to read too much into the successes of Bt corn and herbicide resistant crops and conclude that the current regulation in place is sufficient to control the risks of these and other new crops.
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