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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.
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
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.
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.
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.