Genetically modified (GM) foods
are foods derived
from genetically modified
. Genetically modified organisms have had specific
changes introduced into their DNA by genetic engineering
, using a process of
. These techniques are much more
precise than mutagenesis
breeding) where an organism is exposed to radiation or chemicals to
create a non-specific but stable change. Other techniques by which
humans modify food organisms include selective breeding
and animal breeding
), and somaclonal variation
GM foods were first put on the market in the early 1990s.
Typically, genetically modified foods are transgenic plant
, canola, and cotton seed oil. But
animal products have also been developed. In 2006 a pig was
controversially engineered to produce omega-3 fatty acids
expression of a roundworm gene produced. Researchers have also
developed a genetically-modified breed of pigs that are able to
absorb plant phosphorus more efficiently, and as a consequence the
phosphorus content of their manure is reduced by as much as
Critics have objected to GM foods on several grounds, including
perceived safety issues, ecological
concerns, and economic
concerns raised by
the fact that these organisms are subject to intellectual property
Genetic modification involves the insertion or deletion of genes.
In the process of Cisgenesis
artificially transferred between organisms that could be
conventionally bred. In the process of Transgenesis
genes from a different species are
inserted, which is a form of horizontal gene transfer. In nature
this can occur when exogenous DNA penetrates the cell membrane for
any reason. To do this artificially may require attaching the genes
to a virus or just physically inserting the extra DNA into the
nucleus of the intended host with a very small syringe, or with
very small particles fired from a gene gun. However, other
methods exploit natural forms of gene transfer, such as the ability
of Agrobacterium to transfer genetic material to plants, or the
ability of lentiviruses to transfer genes to animal cells.
The first commercially grown genetically modified whole food
crop was a tomato (called FlavrSavr
), which was modified to ripen without
softening, by a Californian company Calgene
Calgene took the initiative to obtain FDA approval for its release
in 1994 without any special labeling, although legally no such
approval was required. It was welcomed by consumers who purchased
the fruit at a substantial premium over the price of regular
tomatoes. However, production problems and competition from a
conventionally bred, longer shelf-life
variety prevented the product from becoming profitable. A variant
of the Flavr Savr was used by Zeneca to produce tomato paste
which was sold in Europe during
the summer of 1996. The labeling and pricing were designed as a
marketing experiment, which proved, at the time, that European
consumers would accept genetically engineered foods.
Currently, there are a number of food species in which a
genetically modified version exists.
||Properties of the genetically modified variety
||Percent in US
||Percent in world
||Resistant to glyphosate or glufosinate herbicides
||Herbicide resistant gene taken from bacteria inserted into
||Resistant to glyphosate or glufosinate herbicides, Insect
resistance - using Bt proteins some previously used as pesticides
in organic crop production.
Vitamin-enriched corn derived from South African white corn
variety M37W has bright orange kernels, with 169x increase in beta
carotene, 6x the vitamin C and 2x folate.
|New genes added/transferred into plant genome.
|Cotton (cottonseed oil)
||Bt crystal protein gene added/transferred into plant
||Variety is resistant to the papaya ringspot virus.
||New gene added/transferred into plant genome
||Variety in which the production of the enzyme polygalacturonase (PG) is suppressed, retarding
fruit softening after harvesting.
||A reverse copy (an antisense gene) of
the gene responsible for the production of PG enzyme added into
||Taken off the market due to commercial failure.
||Amflora variety produces waxy potato starch composed almost
exclusively of the amylopectin component
||The gene for granule bound starch synthase (GBSS) (the key
enzyme for the synthesis of amylose) was
switched off by inserting antisense copy of the GBSS gene.
||Amflora will be produced solely under contract farming
conditions and not made available on the general market.
||Resistance to herbicides (glyphosate or glufosinate), high
||New genes added/transferred into plant genome
||Resistance to certain pesticides, high-sucrose cane.
||New genes added/transferred into plant genome
||Resistance to glyphosate, glufosinate herbicides
||New genes added/transferred into plant genome
||Produces its own bioinsecticide (Bt toxin)
||Gene from the bacterium Bacillus thuringiensis added to the
||Genetically modified to contain high amounts of Vitamin A
||"Golden rice" Three new genes
implanted: two from daffodils and the
third from a bacterium
In addition, various genetically engineered micro-organisms are
routinely used as sources of enzymes
manufacture of a wide variety of processed foods. These include
from bacteria, which
converts starch to simple sugars, chymosin
from bacteria or fungi that clots milk protein for cheese making,
from fungi which
improves fruit juice clarity.
Growing GM crops
Between 1997 and 2005, the total surface area of land cultivated
with GMOs had increased by a factor of 50, from
(4.2 million acres) to
(222 million acres).
Although most GM crops are grown in North
, in recent years there has been rapid growth in the
area sown in developing
. For instance in 2005 the largest increase in crop
area planted to GM crops (soybeans) was in Brazil
in 2005 versus
in 2004.) There has also been rapid and
continuing expansion of GM cotton varieties in India since 2002.
(Cotton is a major source of vegetable cooking oil and
Fodder|animal feed.) It is predicted that in 2008/9
of GM cotton will be harvested in India
(up more than 100 percent from the previous season).Indian national
average cotton yields of GM cotton were seven times lower in 2002,
because the parental cotton
plant used in
the genetic engineered variant was not well suited to the climate
of India and failed. The publicity given to transgenic trait Bt
insect resistance has encouraged the adoption of better performing
hybrid cotton varieties, and the Bt trait has substantially reduced
losses to insect predation. Though controversial and often
disputed, economic and environmental benefits of GM cotton in India
to the individual farmer have been documented.
In 2003, countries that grew 99% of the global transgenic crops
were the United States (63%), Argentina (21%), Canada (6%), Brazil
(4%), China (4%), and South Africa
(1%). The Grocery Manufacturers of America estimate that 75% of all
processed foods in the U.S. contain a GM ingredient . In
particular, Bt corn, which produces the pesticide within the plant
itself, is widely grown, as are soybeans genetically designed to
tolerate glyphosate herbicides. These constitute "input-traits" are
aimed to financially benefit the producers, have indirect
environmental benefits and marginal cost benefits to
In the US, by 2006 89% of the planted area of soybeans, 83% of
cotton, and 61% maize were genetically modified varieties.
Genetically modified soybeans carried herbicide-tolerant traits
only, but maize and cotton carried both herbicide tolerance and
insect protection traits (the latter largely the Bacillus
Bt insecticidal protein). In the period 2002 to
2006, there were significant increases in the area planted to Bt
protected cotton and maize, and herbicide tolerant maize also
increased in sown area.
Several studies supported by organic growers have claimed that
genetically modified varieties of plants do not produce higher
than normal plants. However,
independent scientific studies have not been able to substantiate
One study by Charles Benbrook, Chief Scientist of the Organic
, found that genetically engineered Roundup Ready
soybeans do not increase yields (Bendrook, 1999). The report
reviewed over 8,200 university trials in 1998 and found that
Roundup Ready soybeans yielded 7-10% less than similar natural
varieties. In addition, the same study found that farmers used 5-10
times more herbicide (Roundup) on Roundup Ready soybeans than on
Coexistence and traceability
The United States and Canada do not require labeling of genetically
modifed foods. However in certain other regions, such as the
European Union, Japan, Malaysia and Australia, governments have
required labeling so consumers can exercise choice between foods
that have genetically modified, conventional or organic origins.
This requires a labeling system as well as the reliable separation
of GM and non-GM organisms at production level and throughout the
whole processing chain. Research suggests that this may prove
the OECD has introduced a "unique identifier" which is given to any
GMO when it is approved. This unique
must be forwarded at every stage of processing. Many
countries have established labeling regulations and guidelines on
coexistence and traceability. Research projects such as Co-Extra
, SIGMEA and Transcontainer are aimed at
investigating improved methods for ensuring coexistence and
providing stakeholders the tools required for the implementation of
coexistence and traceability.
Testing on GMOs in food and feed is routinely done using molecular
techniques like DNA microarrays
. These tests can be based on screening
genetic elements (like p35S, tNos, pat, or bar) or event-specific
markers for the official GMOs (like Mon810, Bt11, or GT73).The
array-based method combines multiplex
and array technology to screen samples for different potential GMOs
, combining different approaches (screening elements,
plant-specific markers, and event-specific markers).
The qPCR is used to detect specific GMO events by usage of specific
elements or event-specific markers. Controls are necessary to avoid
false positive or false negative results. For example, a test for
is used to avoid a false positive in the
event of a virus-contaminated sample.
Several scientists argue that in order to meet the demand for food
in the developing world, a second green
with increased use of GM crops is needed.Raney,
Terri, and Prahbu Pingali. "Sowing A Gene Revolution." Scientific
American September 2007. 11 September 2008
Others argue that there is more than
in the world and that the hunger crisis is caused
by problems in food distribution
and politics, not production, so people should not be offered food
that may carry any degree of risk. This argument assumes that
genetically modified foods present risks not present in traditional
foods, which are demonstrably not free of risk. Recently some
critics have changed their minds on the issue with respect to the
need for additional food supplies.
In 1998 Rowett Research
reported that consumption of potatoes genetically
modified to contain lectin
intestinal effects on rats. Pusztai eventually published a paper,
co-authored by Stanley Ewen, in the journal, The Lancet
. The paper claimed to show that rats
fed on potatoes genetically modified with the snowdrop lectin had
unusual changes to their gut tissue when compared with rats fed on
non modified potatoes. However, the experiment has been criticised
on the grounds that the unmodified potatoes were not a fair control
Economic and political effects
Adoption of genetically-engineered
crops in the United States.
- Many proponents of genetically engineered crops claim they
lower pesticide usage and have brought higher yields and
profitability to many farmers, including those in developing
- The United States has seen a widespread adoption of
genetically-engineered corn, cotton and soybean crops over the last
decade (see figure).
August 2003, Zambia cut off the
flow of Genetically Modified Food (mostly maize) from UN's World Food Programme. This left
a famine-stricken population without food aid.
- In December 2005 the Zambian government changed its mind in the
face of further famine and allowed the importation of GM maize.
However, the Zambian Minister
for Agriculture Mundia Sikatana has insisted that the ban on
genetically modified maize remains, saying "We do not want GM
(genetically modified) foods and our hope is that all of us can
continue to produce non-GM foods."
April 2004 Hugo Chávez announced a
total ban on genetically modified seeds in Venezuela.
January 2005, the Hungarian government announced a ban on importing and
planting of genetic modified maize seeds, which was subsequently
authorized by the EU.
- On August 18, 2006, American exports of rice to Europe were
interrupted when much of the U.S. crop was confirmed to be
contaminated with unapproved engineered genes, possibly due to
accidental cross-pollination with
Traditionally, farmers in all nations saved their own seed from
year to year. Allowing farmers to follow this practice with
genetically modified seed would result in seed developers losing
the ability to profit from their breeding work. Therefore,
genetically-modified seed are subject to licensing by their
developers in contracts that are written to prevent farmers from
following this traditional practice. Many objections to genetically
modified food crops are based on this change.
Enforcement of patents
modified plants is often contentious, especially because of
. In 1998, 95-98 percent of about
10 km2 planted with canola by Canadian farmer
Percy Schmeiser were found to
contain Monsanto Company's patented
Roundup Ready gene although Schmeiser
had never purchased seed from Monsanto.
The initial source
of the plants was undetermined, and could have been through either
gene flow or intentional theft. However, the overwhelming
predominance of the trait implied that Schmeiser must have
intentionally selected for it. The court determined that Schmeiser
had saved seed from areas on and adjacent to his property where
Roundup had been sprayed, such as ditches and near power
Although unable to prove direct theft, Monsanto sued Schmeiser for
piracy since he knowingly grew Roundup Ready
without paying royalties(Ibid). The case made it to the Canadian
Supreme Court, which in 2004 ruled 5 to 4 in Monsanto’s favor. The
dissenting judges focused primarily on the fact that Monsanto's
patents covered only the gene itself and glyphosate resistant
, and failed to cover transgenic plants in their
entirety. All of the judges agreed that Schmeiser would not have to
pay any damages since he had not benefited from his use of the
genetically modified seed.
In response to criticism, Monsanto Canada's Director of Public
Affairs stated that "It is not, nor has it ever been Monsanto
Canada's policy to enforce its patent on Roundup Ready crops when
they are present on a farmer's field by accident...Only when there
has been a knowing and deliberate violation of its patent rights
will Monsanto act."
Future envisaged applications of GMOs are diverse and include drugs
in food, bananas
that produce human vaccines
against infectious diseases
such as Hepatitis B
, metabolically engineered fish that
mature more quickly, fruit and nut trees that yield years earlier,
foods no longer containing properties associated with common
intolerances, and plants that produce new plastics with unique
properties. While their practicality or efficacy in commercial
production has yet to be fully tested, the next decade may see
exponential increases in GM product development
gain increasing access to genomic resources that are applicable to
organisms beyond the scope of individual projects. Safety testing
of these products will also, at the same time, be necessary to
ensure that the perceived benefits will indeed outweigh the
perceived and hidden costs of development.Plant scientists, backed
by results of modern comprehensive profiling of crop composition,
point out that crops modified using GM techniques are less likely
to have unintended changes than are conventionally bred
In the United States, the FDA Center for Food Safety and Applied
Nutrition must approve the nutritional characteristics of GMO foods
on the basis of comparability to conventionally-produced foods. The
table below shows the foods that had received FDA approval as of
As of January 2009 there has only been one human feeding study
conducted on the effects of genetically modified foods. The study
involved seven human volunteers who had their large intestines
removed. These volunteers were to eat GM soy to see if the DNA of
the GM soy transferred to the human gut bacteria. Researchers
identified that three of the seven volunteers had transgenes from
GM soy transferred into their gut bacteria, though none of the gene
transfers occurred during the course of the study. In volunteers
with complete digestive tracts, no recombinant DNA was found.
Anti-GM advocates believe the study should prompt additional
testing to determine its significance.
In the mid 1990s Pioneer Hi-Bred tested the allergenicity of a
transgenic soybean that expressed a Brazil
seed storage protein in hope that the seeds would have
increased levels of the amino acid
methionine. The tests (radioallergosorbent testing, immunoblotting,
and skin-prick testing) showed that individuals allergic to Brazil
nuts were also allergic to the new GM soybean. Pioneer has
indicated that it will not develop commercial cultivars containing
Brazil nut protein because the protein is likely to be an
- Guelph Transgenic Pig Research Program: EnviropigTM an
environmentally friendly breed of pigs that utilizes plant
phosphorus efficiently. November 04, 2005.
- NRC. (2004). Safety of Genetically Engineered Foods: Approaches
to Assessing Unintended Health Effects. National Academies Press.
Free full text.
- FDA Consumer Letter (September 1994): First Biotech Tomato
- GEO-PIE Project - Cornell University
- Shaista Naqvi, et al. Transgenic multivitamin
corn through biofortification of endosperm with three vitamins
representing three distinct metabolic pathways PNAS April 27,
- Richard M. Manshardt ‘UH Rainbow’ Papaya: A
High-Quality Hybrid with Genetically Engineered Disease Resistance.
Cooperative Extension Service/CTAHR, University of Hawaii at
- U.S. Food and Drug Administration Center for Food Safety
and Applied Nutrition, Biotechnology of Food. FDA
Backgrounder: May 18, 1994.
- Amflora - A star(ch) is born: Amylose and
Amylopectin - two sides to one potato.
- Rapeseed (canola) has been genetically engineered to modify its
oil content with a gene encoding a "12:0 thioesterase" (TE) enzyme
from the California bay plant (Umbellularia californica) to
increase medium length fatty acids, see: 
- Need a more specific citation for this data than the ISAAA homepage.
- Economic Impact of Genetically Modified Cotton in
- Comparing the Performance of Official and
Unofficial Genetically Modified Cotton in India
- Genetically Modified Foods and Organisms
- Genetic Engineering: The Future of Foods?
- Adoption of Genetically Engineered Crops in the U.S. USDA
ERS July 14, 2006
- Press Releases 2008
- Organic Farming can Feed The World!
- Trade barriers seen in EU label for bio-engineered ingredients.
(Regulatory and Policy Trends). Business and the Environment 13.11
(Nov 2002): p14(1).
- northwestern.edu Northwestern Journal of Technology
and Intellectual Property Paper on: "Consumer Protection" Consumer
Strategies and the European Market in Genetically Modified Foods
Quote: The recent Trans Atlantic Consumer
Dialogue (TACD) Statement on the WTO decision makes this clear:
"clearly consumers' preference for non-GM food is the true engine
of the market collapse for American crops." and For
instance, Evenson notes that the politicization of GMOs is not
merely a question of labeling as information, but unlabeled GM
products as catalysts in the "globalization backlash."
- CBC Identifying genetically modified products.
Quote: Yet as seen in this report from CBC's Marketplace, no
such labeling law exists in Canada despite numerous surveys
indicating up to 90 per cent of Canadians want mandatory labeling
of GM food. Canada's leading national consumer group does not
support mandatory labeling. It appeared to reverse its stance on
December 3, 2003: http://www.consumer.ca/1626
- Lappe FM, Collins J, Rosset P, and Esparza L
- Boucher D
- Valley, Paul. Strange fruit: Could genetically
modified foods offer a solution to the world's food crisis?
The Independent, 18 April 2009.
- James Randerson interviews biologist Arpad Pusztai
| Education | The Guardian
- Martin Enserink The Lancet Scolded Over Pusztai Paper Science
22 October 1999: Vol. 286. no. 5440, p. 656 DOI
- http://www.ers.usda.gov/Data/BiotechCrops/ US Department of
Agriculture, Economic Research Service. Adoption of Genetically
Engineered Crops in the U.S. July 2, 2008
- Economic Impact of Transgenic Crops in Developing
- Zambia Allows Its People To Eat
- The Peninsula On-line: Qatar's leading English
- World Environment News - Planet Ark
- Venezuela: Chavez Dumps Monsanto - Social and
Economic Policy - Global Policy Forum
- Agriculture Department Probes Rice Flap:
- United States General Accounting Office, Report to the
Chairman, Subcommittee on Risk Management, Research, and Specialty
Crops, Committee on Agriculture, House of Representatives.
Information on Prices of Genetically Modified Seeds in the
United States and Argentina. January 2000
- Federal court of Canada. Monsanto Canada Inc. v. Schmeiser Date: 20010329 Docket:
T-1593-98 Retrieved 26 March 2006.
- Schubert, Robert: "Schmeiser Wants to Take It to The Supreme
Court", CropChoice News, September 9, 2002
- Proteomic profiling and unintended effects in genetically
modified crops, Sirpa O. Kärenlampi and Satu J. Lehesranta
- Hierarchical metabolomics demonstrates substantial
compositional similarity between genetically modified and
conventional potato crops, G S Catchpole and others PNAS October 4,
2005 vol. 102 no. 40 14458-14462
- http://www.gao.gov/new.items/d02566.pdf US GAO. "Genetically
Modified Foods: Experts View Regimen of Safety Tests as Adequate,
but FDA's Evaluation Process Could Be Enhanced." GAO-02-566
Genetically Modified Foods,
- Netherwood et al., "Assessing the survival of transgenic planic
plant DNA in the human gastrointestinal tract," Nature
Biotechnology 22 (2004):2.
- Smith, Jeffrey. Genetic Roulette: The Documented Health Risks
of Genetically Engineered Foods, p.130, 2007
- Julie A. Nordlee, "Identification of Brazil-Nut Allergen in
Transgenic Soybeans," New England Journal of Medicine, 334
- Streit, L.G., L.R. Beach, J.C. Register, III, R. Jung, and W.R.
Fehr. 2001. Association of the Brazil nut protein gene and Kunitz
trypsin inhibitor alleles with soybean protease inhibitor activity
and agronomic traits. Crop Sci. 41:1757–1760.
Cons and Pros of GM food.
- Mark Pollack & Gregory Shaffer, When Cooperation Fails: The International Law and
Politics of Genetically Modified Foods (Oxford University Press
- Mendel in the Kitchen, by Nina Fedoroff and Nancy Marie
- The environmental food crisis A study done by
the UN on feeding the world population (2009)
- Tomorrow's Table: Organic Farming, Genetics, and the Future of
Food, Ronald and Adamchak (2008) ISBN 978-0195301755
- Biotechnology, Agriculture, and Food Security in Southern
Africa Edited by Steven Were Omamo and Klaus von Grebmer (2005)
(Brief and Book available)
- Genetic Roulette: The Documented Health Risks of
Genetically Engineered Foods by Jeffrey M. Smith.
- Beth H. Harrison (2007) Shedding Light
on Genetically Engineered Food: What You Don't Know About the Food
You're Eating and What You Can Do to Protect Yourself
- World Hunger by Brian Kenneth Swain is a new fiction book
concerning the topic of genetically-modified food and some
potential consequences on society. ISBN 978-0595686254
- McHughen, A. Pandora's Picnic Basket: The Potential and Hazards
of Genetically Modified Foods, Oxford University Press, 2000
- Tokar, B.(ed.) Redesigning Life? Zed Books, 2001.
- Let Them
Eat Precaution. How Politics Is Undermining the Genetic Revolution in
Agriculture. By Byrne, J., Conko, G., Entine, J., Gilland, T.,
Hoban, T. H., Moore, P., Natsios, A. S, Newell-McGloughlin, M.,
Paarlberg, R. L., Prakash, C. S., Tucker Foreman, C., Edited by Jon
Entine AEI Press (Washington) 2006. Facets of the GM crop debate
not covered by antagonists to the technology.
- Genetics by Nina V.
Fedoroff and Nancy Marie Brown
- Helena Norberg-Hodge, "The
Pressure to Modernize and Globalize", in The Case Against the
Global Economy and for a Turn Toward the Local 45 (J. Mander
& E. Goldsmith eds., 1996)
- Ellen Ruppel Shell, New
World Syndrome, ATLANTIC
MONTHLY, June 2001
- Vandana Shiva, A World View of
Abundance, ORION, Summer 2000
- Eric Schlosser, Fast Food
Nation: The Dark Side of the All American Meal (2001)
- Michael Pollan, The Futures of
Food: The Industry Has Found a Way to Co-opt the Threat from
Organics and ‘Slow Food.’ Remember the Meal in a Pill?, NY TIMES MAG., Sun., May 4, 2003, at sec.
6, p. 63
- Matt Lee and Ted Lee, The Next Big Flavor: Searching For
the Taste of Tomorrow, id. at 66
- Amanda Hesser, Vintage
Cuts, id. at 72
- Danylo Hawaleshka with Brian Bethune and Sue Ferguson,
Tainted Food, (Kraft to develop
nanoparticles that can change food color, flavor, and nutrient
value to suit a person’s health or palate)
- Gary Ruskin, The Fast Food Trap: How Commercialism Creates
Overweight Children, Mothering Mazagine, Nov./December
- Kate Zernike, Is Obesity the Responsibility of the Body
Politic?, NY TIMES, Sun., November 9, 2003, at sec. 4,
- Carl Hulse, Vote in House Bars Some Suits Citing
Obesity, NY TIMES, Thurs., March 11, 2004, at sec. A.,
- Garcia, Deborah Koons (Director). 2004. The Future of Food.