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Genetically modified (GM) foods = 1650 words Field of study: Genetic engineering and biotechnology Significance: Genetically modified foods are produced through the use of genetic engineering or recombinant DNA technology to crop breeding by which gene(s) from the same or different species is(are) transferred and expressed in a crop that does not naturally harbor the gene(s). While GMOs offer great potential for food production in agriculture, their release has spurred various concerns among the general public. It is vital to examine the GM foods on a scientifically informative manner. Key terms Bt toxin: A toxic compound naturally synthesized by bacterium Bacillus thuringiensis, which kills off insects. Genetic engineering: The manipulation of genetic material for practical purposes; also referred to as recombinant DNA technology, gene splicing or biotechnology GMO: Genetically modified organism—organisms that are created specifically through the use of genetic engineering or biotechnology Herbicide resistance: A trait acquired by crop plants through recombinant DNA technology that enables plants to resist chemicals designed to control weeds Genetically Modified Foods: An Overview GM foods are food products derived from genetically modified organisms (GMOs). GMOs may have genes deleted, added, or replaced for a particular trait. It is one of the most important means by which crop plants will be improved in the future. The advantage of using genetic engineering is quite obvious: it allows individual genes to be inserted into organisms in a way that is both precise and simple. Using molecular tools available, DNA molecules from entirely different species can now be spliced together to form a recombinant DNA molecule. Recombinant DNA molecule can then be introduced into a cell or tissue through genetic transformation. When a particular gene that codes for a trait is successfully introduced to an organism and expressed, we define that organism as transgenic or GMO. Most of the GM crops in production thus far have modified crop protection characteristics, mainly protection against insects and from competition (herbicide resistance). Some have improved nutritional quality and longer shelf life. Yet others under development will be to lift the yield cap not possible to overcome by conventional means. Because of the direct access to and recombination of genetic material from any source, the normally existed reproductive barrier among different species can now be circumvented. This lends great power for creating transgenic animals and plants potentially useful for mankind, but also posts possibility for misuses and fear for unintended outcomes. 1 Conceivable Benefits of GM Foods The potential benefits of using genetic engineering to develop new cultivars are evident. Crop yields can be increased by introducing genes that increase the crop’s resistance to various pathogens or herbicides and enhance its tolerance to various stresses. The increased food supply is vital to support a growing population with a shrinking land. One well known example is the introduction of Bt gene from the bacterium Bacillus thuringiensis to several crops including corn, cotton and soybean. When Bt gene is transferred to plants, the plant cells produce a protein toxic to some insects and hence become resistance to these insects. The grains of Bt maize were also found to contain low mycotoxin thus exhibit better food safety than non-GM corns. Another example is the successful insertion of gene resistant to herbicide glyphosate, reducing the production cost and increase the grain purity. Food quality can be improved through GM as well. Soybean and canola with reduced saturated fats (healthier oil) have been developed. Alterations in the starch content of potatoes and the nutritional quality of protein in maize kernels are being developed. More precise gene transfer is also being used to produce desirable products that the plant does not normally make. The potential products include pharmaceutical proteins (e.g., vaccines), vitamins and plastic compounds. ―Golden rice‖ has been engineered to produce significantly higher vitamin A precursors (β-carotene). This GM rice plays an important role to alleviate the vision loss and/or blindness caused by vitamin A deficiency among those who consume rice as their main staple food. Attempts are being made to increase nitrogen availability, a limiting factor in crop production, by transferring genes responsible for nitrogen fixation into crops such as wheat and maize. In addition, the reduced use of fertilizer, insecticide, and herbicide not only saves billions of dollars in costs, but also alleviates the damage to wild lives and ecosystems. Concerns about GM Foods As with any other technological innovations, use of genetic engineering in crop breeding and production does not come with zero risk or without controversies. These questions are common: I don’t know what I am eating; is this food safe; how well are GM foods tested; why not label it; are there any new toxins and allergens in GM foods? Although most of these questions are understandable, the recent uproar, particularly in Great Britain and Europe, concerning the GM crops/foods were blown out of proportion. Several reasons may be responsible for the unrealistic fears towards GM foods. First is unfamiliarity with the technology and lack of reliable information in the general public. Most ordinary citizens simply don’t understand much about the genetic engineering technology. The scientists will need to step up their effort to educate general public. Secondly, most people are not aware of the strict regulation over GM research and active safeguards by the government. Research and chemical analyses by many scientists working with FDA, USDA or independently have concluded that biotechnology is a safe means of producing foods. Thousands of tests over 15 years in US, and the consumption 2 of GM foods in US for four years have not found harmful effects related to GM foods. Most food safety problems are due to handling (e.g. microbial contamination), GM and non-GM foods alike. The third reason for the societal concern rooted in the negative media opinion, opposition by activists and mistrust of the industry. Most current complaints about GM foods can be categorized into three major areas: the possible detrimental health effects, the potential environmental threats such as ―super weeds‖, and the social, economical and ethical implications of genetic engineering. Broader Issues in Biotechnology In response to the demands of activist groups, EU and its member states have adopted very strict regulations over the import and release of GMOs. Some activists have taken extreme measure to destroying field plots and even firebombing a research laboratory. Although the majority of the public don’t agree with the extreme measures taken by some activists, some continue to push for mandatory labeling of all foods whose components have derived from GMOs. Activist groups and media also continue to create myths and release misinformation regarding GM foods: GMOs have no benefit to the consumer, it may harm environment, it’s unsafe to eat, the only beneficiary is big corporations, it does not benefit small farmers, it will drive organic farmers out of business, etc… Although some concerns are genuine, one should not ignore the fact that safety is a relative concept. Agriculture and animal husbandry have inherent dangers, as do the consumption of their products, regardless of GM or non-GM foods. GM crops and foods are being subjected to more safety checks and tighter regulation than their non-GM counterparts. Through extensive studies and analyses, both USDA and EU have found no perceptible difference between conventional and GM foods. Of course, one cannot assure absolute, zero risk on any drugs or food products, regardless of how they are produced. The demand for zero risk is more of an emotional reaction than realistically possible. Mandatory labeling on all GM foods is both impractical and technically difficult. It would drive the food price to a much higher level than consumer is willing to pay. Farmers and food industry would have to sort every GMO and store and process them separately. Realizing the complexity, federal agencies like FDA and USDA have recommended a voluntary labeling system by which the organic and nonGM food products can be marked for consumers who are willing to pay the premium. It seems to be a fair policy for all parties involved. Where Are We Going From Here? Development of new crops is vital for the future of the world. Since conventional breeding cannot keep up with the population explosion, biotechnology may be the best tool we can use to produce a greater diversity and high quality of safe food on less land, while conserving soil, water and genetic diversity. To ensure the safety and success of GM crops, scientists and regulators will need to have open and honest communications with the public, building trust through better education and more effective regulatory oversights. In the meantime, the media will also need to convey more credible, balanced information to the public. 3 As Nobel laureate Norman Borlaug states ―I now say that the world has the technology that is either available or well advanced in the research pipeline to feed a population of 10 billion people. The more pertinent question today is: Will farmers and ranchers be permitted to use this new technology.‖ Ming Y. Zheng See also: Further Reading Apel, Andrew et al. October 2002. To die or not to die? This is the problem. Comments to a study: What is the impact of GMOs on sustainable agriculture in Zambia? You get the chance to see both sides of the story on GMO. http://www.agbioworld.org/. Borlaug, Norman E. 2000. Ending world hunger. The promise of biotechnology and the threat of antiscience zealotry. Plant Physiology 124: 487-490. The father of ―Green Revolution‖, Nobel laureate speaks of unwavering support for GMOs. Fresco, Louise O. September 2001. Genetically modified organisms in food and agriculture: Where are we? Where are we going? Keynote address – Conference on ―Crop and Forest Biotechnology for the Future‖p.1-7. Royal Swedish Academy of Agriculture and Forestry, Falkenberg, Sweden. Fascinating and informative perspectives on GM foods by an EU scientist. Potrykus, Ingo. 2001. Golden rice and beyond. Plant Physiology 125: 1157-1161. The originator of the wonder rice presents scientific, ethical, intellectual, and social challenges of developing and using the GMOs. Illuminating and insightful. USDA. 4