What is a GMO?
The term "GMO" stands for "genetically modified organism." Most often it refers to an agricultural plant, such as cotton or maize that has had its DNA modified using a process called "genetic engineering."
What are some examples of GMOs?
One example would be a maize plant engineered to contain a gene that makes the cells of the plant hard for certain insects to digest. Another example is a rice plant (called "Golden Rice") that has been engineered to contain several new genes that provide more B-carotene, and hence enriched in Vitamin A, good for preventing loss of human eyesight.
In GMOs, what is it exactly that has been modified?
It is the DNA of a plant that has been modified. DNA stands for Deoxyribo-Nucleic Acid. All living things � including plants and people have molecules of DNA in their cells. These DNA molecules carry the genetic information that tells a cell how to grow. Scientists discovered the shape and structure of these DNA molecules in 1953.
How is the DNA of a GMO modified?
Modifying the DNA of plants is something farmers have been doing for a long time. When plants were first "domesticated" into agricultural crops, it was because their DNA had been modified over many hundreds of years through traditional processes such as seed selection by farmers, and then later through controlled breeding by scientists called "plant breeders." The DNA is modified whenever plants reproduce sexually, which mixes the genes of the two parents together in the offspring. By controlling this process of sexual reproduction among plants, over the years, farmers and scientists transformed wild plants into the crop plants grown by farmers today. GMOs take these traditional crop plants one step farther, by making further changes in their DNA using a technique called "genetic engineering," a technique first developed in 1973. This technique does not rely on sexual reproduction; instead it moves individual genes with desired traits directly from source organisms into the living DNA of target or host organisms, which thus become "GMOs". If the transformed host plant then reproduces sexually, its seeds will inherit the newly added DNA, and they will also be referred to as GMOs. What makes GMOs different from conventionally improved plants, is not the fact that they have been modified, but instead the additional method that has been used to modify them.
What agricultural plants are now available in GMO varieties?
Scientists have been using genetic engineering to modify commercial agricultural crop plants since the early 1980s. It was easiest for them to begin with broad-leaved plants such as tobacco and tomato. Narrow leaved crops such as rice and maize were not successfully transformed into GMOs until the late 1980s. By the late 1990s, however, GMO varieties had been developed for nearly every significant crop species. By 1997, more than 60 different crops had been transformed into GMO varieties, and field trials of these GMOs had taken place in 45 different countries. By the end of 1997, 48 different transgenic crop products (involving 12 crops and six different transgenic traits) had been approved in at least one country for commercial use by farmers.
Which countries are growing GMO crops commercially?
GMOs were first approved for planting in 1994-95, and as of 2006 a total of 22 countries (11 developing, 11 industrial) were growing at least some GMOs commercially. Eight countries were growing GMOs commercially on at least .5 million hectares of cropland: the United States, Argentina, Brazil, Canada, China, Paraguay, India, and South Africa.
Farmers in most European countries do not grow GMOs. In the European Union (EU) nine different GMO crop products or plants � mostly varieties of maize, soybeans, and oilseeds were approved for planting from 1994-1998. Today six EU countries including Spain, Germany, France, Portugal, Czech Republic and Slovakia are growing significant quantities of GM crops.
Farmers in many developing countries also do not yet grow GMOs. In Africa, the only country so far to grow GMOs commercially is South Africa. In Asia, The Philippines, China and India are leading growers of GM crops commercially.
Farmers in most European countries do not grow GMOs. In the European Union (EU) nine different GMO crop products or plants � mostly varieties of maize, soybeans, and oilseeds were approved for planting from 1994-1998. Today six EU countries including Spain, Germany, France, Portugal, Czech Republic and Slovakia are growing significant quantities of GM crops.
Farmers in many developing countries also do not yet grow GMOs. In Africa, the only country so far to grow GMOs commercially is South Africa. In Asia, The Philippines, China and India are leading growers of GM crops commercially.
What are GMOs good for?
Almost all of the transgenic crops currently being grown commercially have been designed to provide benefit to farmers by reducing the cost or effort required to control insect pests, plant diseases, or weeds. These "first generation" GM crops lower production costs for farmers, but the crop itself is not substantially different for consumers either in appearance, taste, or nutritional value. A "second generation" of GM plants designed with new traits of direct value to consumers is now beginning to appear. A "third generation" of GMOs with greater abilities to resist abiotic stress � such as drought, or heat, or salt is emerging from the research pipeline as well.
The greatest benefits from planting GMOs have so far been realized by farmers in the United States, China, Argentina, India, South Africa and Brazil where more GMOs are planted. The leading GM crops grown commercially are Maize, Cotton, Canola and Soybean.
The greatest benefits from planting GMOs have so far been realized by farmers in the United States, China, Argentina, India, South Africa and Brazil where more GMOs are planted. The leading GM crops grown commercially are Maize, Cotton, Canola and Soybean.
Can small farmers in developing countries also benefit from planting GMOs?
The developing country farmers are most likely to benefit from the GMOs now available are farmers that grow maize, cotton, or soybeans, and those looking for new weed and insect control options. Many small cotton farmers in the developing world could gain from GMOs. In 2006, 9.3 million small farmers in developing countries grew GM crops. The Bt cotton farmers in China for example realize substantial economic gains according to independent surveys. A 1999-2001 survey revealed an average 24 percent yield increase when GMO cotton was planted, compared to conventional non-GMO cotton, and an average net economic gain of $470 per hectare compared to non-GMO cotton growers.
Would small farmers in Africa be able to benefit from planting GMOs?
Reliable data on the profitability of GMO planting in Africa is limited to just South Africa, the only country in Africa to have allowed commercial planting of any GMOs so far. In South Africa, one widely cited case in which small farmers have profited is the case of small cotton farmers in Makhathini Flats, in KwaZulu Natal. These farmers have been allowed by their government to plant GMO cotton since 1997/98, and one study in 2001 showed that when they switched from conventional to GMO cotton they suffered less insect damage, sprayed fewer insecticides, and enjoyed an average net income gain of $50 per hectare per season.
African farmers might also benefit from planting GMO maize, to protect against insect pests such as stem borers. South Africa first approved the planting of GMO yellow maize in 1997, and by 2002 roughly 20 percent of that nation's yellow maize crop was GMO, with the net income of farmers who planted GM increasing on average by $27 per hectare per year, under non-irrigated conditions. GMO white maize was introduced in South Africa in 2001. By 2005 GMO varieties were planted on roughly 9 percent of total white maize area and 26 percent of yellow maize area.
African farmers might also benefit from planting GMO maize, to protect against insect pests such as stem borers. South Africa first approved the planting of GMO yellow maize in 1997, and by 2002 roughly 20 percent of that nation's yellow maize crop was GMO, with the net income of farmers who planted GM increasing on average by $27 per hectare per year, under non-irrigated conditions. GMO white maize was introduced in South Africa in 2001. By 2005 GMO varieties were planted on roughly 9 percent of total white maize area and 26 percent of yellow maize area.
Do private multinational companies control GMOs?
In many developing countries, GMOs are being developed not by private companies but by public sector government research institutes (such as KARI, in Kenya). These national agricultural research institutes often have permission to sell the GMO seeds they are developing locally without paying any fees to any foreign holders of patents on the technology, and the local farmers that get these seeds can also save, exchange, and replant them without restriction, in keeping with the "farmers' privileges" that are recognized in nearly all local intellectual property laws.
How will farmers in Africa be able to get access to GMO seeds?
Once the sale of GMO seeds has been approved by a government in Africa, the problem of getting access to GMO seeds will not be so different from the problem of getting access to improved varieties of non-GMO seeds. Hybrid varieties of maize, for example, typically must be purchased anew every year if the desired hybrid trait isn�t to be weakened. GMO hybrids also will most likely be purchased anew every year. On the other hand, openly pollinated GMO varieties can be replanted just as readily as non-GMO open pollinated varieties (OPVs).
Do GMOs carry "terminator genes" that make the seeds sterile?
Currently, there are no GMOs on the market with so called "terminator genes" that make seeds sterile, and there never have been. Scientists at the U.S. Department of Agriculture did conceptualize and patent a GMO technology in the 1990s that would have sterilized the seeds of a plant late in its development, so that the seeds would have value for consumption but not replanting.
Are there risks to planting or eating GMOs?
Many groups still warn against the possible risks that might be associated with GMOs. This was understandable ten years ago, when the technology was still relatively new. But now, after a decade of wide use without any scientific evidence of new risks, the safety fears that still exist are harder to credit.
GMOs must be tested for known risks to human health and the environment before government regulators approve them for commercial use. Large numbers of GMOs have now passed these tests and have been grown and consumed widely for a decade. To date, none of these approved GMOs has been shown to pose any increased risk to human health or to the environment, compared to the conventional non-GMO version of the same plant. This is a conclusion that has now been reached by a considerable number of scientific bodies, including the following:
GMOs must be tested for known risks to human health and the environment before government regulators approve them for commercial use. Large numbers of GMOs have now passed these tests and have been grown and consumed widely for a decade. To date, none of these approved GMOs has been shown to pose any increased risk to human health or to the environment, compared to the conventional non-GMO version of the same plant. This is a conclusion that has now been reached by a considerable number of scientific bodies, including the following:
- In 2001 the Research Directorate General of the European Union (EU) released a summary of 81 separate scientific studies conducted over a 15 year period (all financed by the EU rather than private industry) aimed at determining whether GM products were unsafe, insufficiently tested, or under-regulated. This study concluded: "Research on GM plants and derived products so far developed and marketed, following usual risk assessment procedures, has not shown any new risks on human health or the environment..." (Kessler, Charles, and Ioannis Economidis, eds. 2001. EC-Sponsored Research on Safety of Genetically Modified Organisms: A Review of Results. Luxembourg: Office for Official Publications of the European Communities.)
- In December 2002, the French Academies of Sciences and Medicine issued a report that said, "There [had] not been a health problem . . . or damage to the environment" from GM crops (French Academy of Sciences. 2002. "GM Plants: Reporting on the Science and Technology." http://www.academie-sciences.fr ).
- In May 2003, the Royal Society in London presented to a government-sponsored review in the United Kingdom two submissions that found no credible evidence that GM foods were more harmful than non-GM foods (Royal Society. 2003. Royal Society Submission to the Government�s GM Science Review. Policy Document 14/03.http://www.royalsoc.ac.uk/displaypagedoc.asp?id=11476).
- In March 2004, the British Medical Association (BMA) endorsed the finding of the Royal Society (�Genetically Modified Foods and Health: A Second Interim Statement. British Medical Association. London, March 2004).
- In May 2004, the Food and Agriculture Organization (FAO) of the United Nations issued a 106 page report summarizing the evidence drawn largely from a 2003 report of the International Council for Science (ICSU) � that "to date, no verifiable untoward toxic or nutritionally deleterious effects resulting from the consumption of foods derived from genetically modified foods have been discovered anywhere in the world". On the matter of environmental safety, this same FAO report found that the environmental effects of the GM crops approved so far, including effects such as gene transfer to other crops and wild relatives, weediness and unintended adverse effects on nontarget species (such as butterflies) - have been similar to those that already existed for conventional agricultural crops.
How strictly are GMOs regulated?
GMOs tend to be regulated country-by-country, although the European Union also operates a coordinated region-wide approval and regulatory system for GMOs. Given the strong safety record associated with all the GMOs that have been approved so far, current levels of regulation would seem more than adequate.
Internationally, the most important regulatory agreement governing GMOs is the 2000 Cartagena Protocol to the Convention on Biological Diversity (CBD), which entered into force in September 2003. This Protocol requires that national governments adopt a minimum set of information sharing and consent procedures when exporting or importing some living GMOs (LMOs)
Internationally, the most important regulatory agreement governing GMOs is the 2000 Cartagena Protocol to the Convention on Biological Diversity (CBD), which entered into force in September 2003. This Protocol requires that national governments adopt a minimum set of information sharing and consent procedures when exporting or importing some living GMOs (LMOs)
What do national regulations consist of?
National regulatory systems for GMOs are designed first to assess and then to manage risks in two areas: safety for human and animal consumption ("food safety") and safety to the biological environment (commonly called "biosafety"). Risk assessments for new GMO plants are conducted on a case-by-case basis using scientific evidence generated according to standard protocols. The testing typically is paid for by the research institute or the private company seeking regulatory approval for the GMO. This evidence will then usually be scrutinized by a national technical committee (often called a "national biosafety committee"), composed of specialists from the research community (including institutes and universities) plus representatives of all relevant government ministries (e.g., science and technology, health, agriculture, environment). Separate approvals are typically required first to bring a new GMO into the country, then to grow it in a confined area for research purposes, and then to distribute it for commercial planting over a wide area.
How are GMOs assessed for food safety?
International bodies such as the World Health Organization (WHO) and FAO endorse the practice of allowing GMO foods on the market if scientific testing has shown them to be "substantially equivalent" to non-GMO versions of the same food. The tests used to establish this level of food safety include feeding the food to laboratory rodents to gather data regarding its toxicity, digestivity, and allergenicity and nutrient properties.
As an example of how this process works, the European Food Standards Authority (EFSA) recently gave its approval to a new GMO maize variety (one that provides resistance to corn rootworm pests) after it had seen the results of a 90-day rat feeding study carried out by an independent toxicology facility complying with Good Laboratory Practice standards. The results of this feeding study were reviewed by toxicology experts at this facility, plus experts at EFSA, plus independent national toxicology experts from New Zealand, Italy, Germany, and England.
European regulatory authorities found no convincing evidence in this data of any new risks to human or animal health from this new GMO variety of maize. Similar procedures had led to similar conclusions in the United States, Canada, Japan, Korea, Taiwan, the Philippines, Russia, Australia, New Zealand, and Mexico, where this new GMO variety had also been approved by technical regulators as safe for human consumption.
As an example of how this process works, the European Food Standards Authority (EFSA) recently gave its approval to a new GMO maize variety (one that provides resistance to corn rootworm pests) after it had seen the results of a 90-day rat feeding study carried out by an independent toxicology facility complying with Good Laboratory Practice standards. The results of this feeding study were reviewed by toxicology experts at this facility, plus experts at EFSA, plus independent national toxicology experts from New Zealand, Italy, Germany, and England.
European regulatory authorities found no convincing evidence in this data of any new risks to human or animal health from this new GMO variety of maize. Similar procedures had led to similar conclusions in the United States, Canada, Japan, Korea, Taiwan, the Philippines, Russia, Australia, New Zealand, and Mexico, where this new GMO variety had also been approved by technical regulators as safe for human consumption.
Can developing countries afford the costs of testing?
When screening new GMOs for food safety risks, authorities in developing countries with limited technical capacity have the option of monitoring, recognizing, and then adopting the findings of regulatory authorities in other countries that they trust. For example, African countries could approve any GMO that had been tested and approved by EFSA. Developing countries should feel secure approving what others with stronger testing capabilities have already approved, given that the human biology of food digestion varies so little from one region or population to the next.
How are GMOs assessed for biological safety?
GMO plants are screened for environmental risks on a case-by-case basis, first by growing them within fully contained greenhouses, and then by growing them in confined or isolated field trials, and finally in large scale field trials. The process can take several years. Monitoring for biosafety can continue after an approval for commercial planting is given. If necessary, approvals may be limited to just some parts of a country, and they can be made conditional on the planting nearby of non-GMO "refuge" crops, to slow the emergence of GMO-resistant pest populations.
Does GMO maize pollen kill monarch butterflies?
In 1999 a scientist at Cornell University in the United States published the results of an experiment demonstrating that the caterpillars of monarch butterflies could die if forced in a laboratory to eat milkweed coated with pollen from GMO maize. This widely publicized study raised fears that the drifting pollen from large scale plantings of GMO maize might kill valuable "non-target" insects, and thus reduce biodiversity.
In response to this concern, subsequent studies were undertaken by six independent research teams in the United States to examine closely the impacts of GMO maize pollen on non-target species under actual field conditions, rather than in a laboratory. In 2001 the results of these follow-up studies were published in the Proceedings of the National Academy of Sciences of the United States. All the studies found that under field conditions GMO maize pollen posed a "negligible" risk to monarch butterfly larvae. This was because the amount of pollen likely to be consumed under field conditions was so little as to be non-toxic. A greater risk to butterflies has been the spraying of pesticides on fields of non-GMO crops.
In response to this concern, subsequent studies were undertaken by six independent research teams in the United States to examine closely the impacts of GMO maize pollen on non-target species under actual field conditions, rather than in a laboratory. In 2001 the results of these follow-up studies were published in the Proceedings of the National Academy of Sciences of the United States. All the studies found that under field conditions GMO maize pollen posed a "negligible" risk to monarch butterfly larvae. This was because the amount of pollen likely to be consumed under field conditions was so little as to be non-toxic. A greater risk to butterflies has been the spraying of pesticides on fields of non-GMO crops.
Do GMOs reduce biodiversity?
All domesticated farm crops, both GMO and non-GMO, reduce the space and habitat available for wild species, and in that sense all crops do tend to reduce biodiversity. A few GMO crops may do this slightly more than their conventional counterparts. In 2003 the UK released data from actual farm fields planted with herbicide-tolerant GMO maize, sugarbeets, and oilseed rape, compared to data from fields where non-GMO varieties of the same crops were planted and conventionally grown.
This comparison showed that in fields of sugarbeets and oilseed rape there were slightly fewer weeds in the GMO fields than in the non-GMO fields. This was because the weeds could be killed more efficiently in the fields with the herbicide-tolerant GMO crops. Fewer weeds and more efficient herbicide use are precisely the advantages that farmers in the UK seek when they consider the use of herbicide-tolerant GMO crops, of course. To refer to fewer weeds in a farm field as a "loss of biodiversity" tends to ignore the purpose of crop farming itself.
Some GMOs may actually increase biodiversity in the farm field. When farmers plant insect-resistant Bt varieties of GMO crops, it usually allows them to control pest damage while spraying fewer chemical insecticides. This protects all the non-target insects in the field, all except those eating the crop itself. So Bt crops tend to produce greater biodiversity in the field compared to insecticide spraying on conventional crops.
This comparison showed that in fields of sugarbeets and oilseed rape there were slightly fewer weeds in the GMO fields than in the non-GMO fields. This was because the weeds could be killed more efficiently in the fields with the herbicide-tolerant GMO crops. Fewer weeds and more efficient herbicide use are precisely the advantages that farmers in the UK seek when they consider the use of herbicide-tolerant GMO crops, of course. To refer to fewer weeds in a farm field as a "loss of biodiversity" tends to ignore the purpose of crop farming itself.
Some GMOs may actually increase biodiversity in the farm field. When farmers plant insect-resistant Bt varieties of GMO crops, it usually allows them to control pest damage while spraying fewer chemical insecticides. This protects all the non-target insects in the field, all except those eating the crop itself. So Bt crops tend to produce greater biodiversity in the field compared to insecticide spraying on conventional crops.
When GMOs are planted in the environment do they "escape" human control and become invasive?
The hypothetical risk that GMO crops could somehow escape human control and spread invasively in the natural environment has never been demonstrated, and is fundamentally implausible. GMO crops share an important trait with non-GMO agricultural plants: they are all domesticated species, not wild species, meaning they have lost their ability to survive and compete well in the wild without support from human hands. They have been developed to thrive only when given intensive human care (soil preparation, fertilization, irrigation, weeding, pest control, etc.). Thus, similar to non-GMO crop plants, these GMO crops will tend to die out if left alone within a wild ecosystem. It is not domesticated agricultural crops (GMO or otherwise) that tend to become invasive species in rural ecosystems; instead the greatest threats of "bioinvasion" tend to come from wild "exotic" species introduced into a new ecosystem where there are no natural biological controls for that species.
Does the planting of GMO crops "contaminate" other crops?
It is only possible for GMO pollen to "contaminate" plants of the same species, so pollen drift from GMO maize can fertilize non-GM maize fields, but not any other species of plant. If a country plants GMO maize, there is no biological possibility that its cotton, or beans, or coffee, or cassava will become tainted with GM traits.
Has GMO maize "contaminated" traditional maize fields in Mexico?
In 2001, a biologist from the University of California at Berkeley published a paper presenting evidence that GMO maize genes had mixed with traditional varieties of maize ("landraces") being grown by farmers in remote areas in Oaxaca, Mexico. Mexico's National Institute of Ecology and its interagency National Biodiversity Council then did an independent sampling of maize in the region and confirmed some presence of corn with GMO traits. This "contamination" of traditional varieties was of uncertain origin, since it was not legal to plant GMO maize in Mexico at that time. The extent of this contamination remains in doubt. In 2005, a peer-reviewed follow-up study found no evidence of genes from GM maize in any of 150,000 seeds that were sampled from 870 plants in Oaxaca in 2003 and 2004.
Would the spread of GMO traits into traditional maize crops be a serious problem?
The presence of some GMO genes in a field of traditional maize might pose a commercial risk, if consumers do not wish to buy GM maize, but there is little evidence that it could constitute a significant risk to the environment, or to traditional "landrace" varieties. The spread of a GMO trait to a more traditional variety will not produce an invasive species, since both the traditional maize and the GMO maize are domesticated plants that need human intervention to survive in the wild.
If keeping traditional landrace varieties "pure" is the goal, then it would be necessary to stop planting all new commercial varieties of maize, including both GMO and non-GMO varieties, because both can exchange pollen with traditional varieties. The image of traditional varieties that are "pure" is incorrect in any case, since these traditional varieties are constantly evolving under the care of farmers that save and exchange seeds on a selective basis, looking only for traits that they like. If the planting of GMO (or non-GMO) commercial maize seeds results in a spread of traits that farmers do not like, the farmers will be able to eliminate the trait by de-selecting the seeds that carry those traits.
If keeping traditional landrace varieties "pure" is the goal, then it would be necessary to stop planting all new commercial varieties of maize, including both GMO and non-GMO varieties, because both can exchange pollen with traditional varieties. The image of traditional varieties that are "pure" is incorrect in any case, since these traditional varieties are constantly evolving under the care of farmers that save and exchange seeds on a selective basis, looking only for traits that they like. If the planting of GMO (or non-GMO) commercial maize seeds results in a spread of traits that farmers do not like, the farmers will be able to eliminate the trait by de-selecting the seeds that carry those traits.
Do GMOs contaminate the growing of "organic" crops?
Farmers who want their crops to be certified as "organic" are currently not allowed to plant GMO varieties. If pollen drifts in from GMO crops nearby, will the crops of these organic farmers then contain seeds with GMO genes? This difficulty of "co-existence" between GMO crops and non-GMO organic crops is currently being debated, particularly in Europe. Some organic growers cite this problem as a reason to ban the planting of GMOs entirely.
Since it is only possible for GMO pollen to spread to plants of the same species, the amount of contamination that can occur is usually quite limited. For example, on an organic farm next to a GMO maize field, the only risk of contamination would be to maize. Very few of the other crop species that are now being grown organically (especially fruits and vegetables) are currently available in GMO form, which eliminates the possibility of contamination.
Since it is only possible for GMO pollen to spread to plants of the same species, the amount of contamination that can occur is usually quite limited. For example, on an organic farm next to a GMO maize field, the only risk of contamination would be to maize. Very few of the other crop species that are now being grown organically (especially fruits and vegetables) are currently available in GMO form, which eliminates the possibility of contamination.
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