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Genetically Modified Food

Genetically modified (GM) foods are foods derived from genetically modified organisms. Genetically modified organisms have had specific changes introduced into their DNA by genetic engineering techniques. These techniques are much more precise than mutagenesis (mutation 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 (plant 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 products: soybean, corn, canola, and cotton seed oil. Animal products have also been developed, although as of July 2010 none are currently on the market. In 2006 a pig was controversially engineered to produce omega-3 fatty acids through the expression of a roundworm gene. 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 60%.

Critics have objected to GM foods on several grounds, including possible safety issues, ecological concerns, and economic concerns raised by the fact that these organisms are subject to intellectual property law.

Method

Genetic modification involves the insertion or deletion of genes. In the process of cisgenesis, genes are 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 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, and the ability of lentiviruses to transfer genes to animal cells.

Development

The first commercially grown genetically modified whole food crop was a tomato (called FlavrSavr), which was modified to ripen without softening, by Calgene, later a subsidiary of Monsanto. 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 tomato produced using similar technology to 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 (percent modified are mostly 2009/2010 data.

In addition, various genetically engineered micro-organisms are routinely used as sources of enzymes for the manufacture of a variety of processed foods. These include alpha-amylase from bacteria, which converts starch to simple sugars, chymosin from bacteria or fungi that clots milk protein for cheese making, and pectinesterase from fungi which improves fruit juice clarity.

Growing GM crops

Between 1997 and 2009, the total surface area of land cultivated with GMOs had increased by a factor of 80, from 17,000 km2 (4.2 million acres) to 1,340,000 km2 (331 million acres).

Although most GM crops are grown in North America, in recent years there has been rapid growth in the area sown in developing countries. For instance in 2009 the largest increase in crop area planted to GM crops (soybeans) was in Brazil (214,000 km2 in 2009 versus 158,000 km2 in 2008.)[13] 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 animal feed.) In 2009 84,000 km2 of GM cotton were harvested in India (87 percent of cotton produced in India was based on GM cotton).

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 2009, countries that grew 95% of the global transgenic crops were the United States (46%), Brazil (16%), Argentina (15%), India (6%), Canada (6%), China (3%), Paraguay (2%) and South Africa (2%). 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 consumers.

In the US, by 2009/2010, 93% of the planted area of soybeans, 93% of cotton, 86% of corn and 95% of the sugar beet 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 thuringiensis 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.

Legal issues in the US

On 21 June 2010, the US Supreme Court has issued its first ruling in regard to a GM crop. This was a ruling in regard to Roundup Ready alfalfa. The case goes back to 2006, when organic farmers, concerned about the impact of GM alfalfa on their crops, sued Monsanto. In response, the California Northern District Court ruled that the United States Department of Agriculture (USDA) was in error when it approved the planting of Roundup Ready alfalfa. According to the presiding judge, the law required the USDA to first conduct a full environmental study, which it had not done. It was the concern of the organic growers that the GM alfalfa could cross-pollinate with their organic alfalfa, making their crops unsalable in countries that forbid the growing of GM crops.

The impact of the current US Supreme Court ruling is somewhat unclear, with both sides appearing to claim victory. While Monsanto can claim technical victory in the case, various other issues still remain open, and will likely be litigated in the future. Meanwhile, the planting of GM alfalfa currently remains halted in the US, and it is unclear when it may resume.

Sugar beets

In 2009-2010, the United States District Court for the Northern District of California has been considering the case involving the planting of genetically modified sugar beets. This case involves Monsanto's breed of pesticide-resistant sugar beets. Earlier in 2010, Judge Jeffrey S. White allowed the planting of GM sugar beets to continue, but he also warned that this may be blocked in the future while an environmental review was taking place. Finally, on 13 August 2010, Judge White ordered the halt to the planting of the genetically modified sugar beets in the US. He indicated that "the Agriculture Department had not adequately assessed the environmental consequences before approving them for commercial cultivation." The decision was the result of a lawsuit organised by the Center for Food Safety, a US non-governmental organisation that is a critic of biotech crops.

Crop yields

Some scientific studies have claimed that genetically modified varieties of plants do not produce higher crop yields than normal plants.

One study by Charles Benbrook, Chief Scientist of the Organic Center, 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 conventional ones.

However, research published in Science has shown that genetically modified crops can increase yield while reducing the number of applications of insecticides.

Still more recently, the Union of Concerned Scientists summarized numerous peer-reviewed studies on the yield contribution of genetic engineering in the United States. This report examined the two most widely grown engineered crops—soybeans and maize. Unlike many other studies, this work separated the yield contribution of the engineered gene from that of the many naturally occurring yield genes in crops.

The report found that engineered herbicide tolerant soy and maize did not increase yield at the national, aggregate level. Maize engineered with Bt insect resistance genes increased national yield by about 3 to 4 percent. Engineered crops increased net yield in all cases.

The study concluded that in the United States, other agricultural methods have made a much greater contribution to national crop yield increases in recent years than genetic engineering. United States Department of Agriculture data record maize yield increases of about 28 percent since engineered varieties were first commercialized in the mid 1990s. The yield contribution of engineered genes has therefore been a modest fraction—about 14 percent—of the maize yield increase since the mid 1990s.

Coexistence and traceability

The United States and Canada do not require labeling of genetically modified 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.

For traceability, the OECD has introduced a "unique identifier" which is given to any GMO when it is approved. This unique identifier must be forwarded at every stage of processing.[citation needed] 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.[citation needed]

Detection

Testing on GMOs in food and feed is routinely done using molecular techniques like DNA microarrays or qPCR. 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 PCR 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 primers for screening elements or event-specific markers. Controls are necessary to avoid false positive or false negative results. For example, a test for CaMV is used to avoid a false positive in the event of a virus contaminated sample.

PLU codes

A Price Look-Up code beginning with the digit 8 indicates genetically modified food.

Controversy

Main article: GM food controversy

While it is evident that there is a food supply issue, the question is whether GM can solve world hunger problems, or even if that would be the best way to address the issue. Several scientists argue that in order to meet the demand for food in the developing world, a second green revolution with increased use of GM crops is needed. Others argue that there is more than enough food in the world and that the hunger crisis is caused by problems in food distribution and politics, not production. Recently some critics have changed their minds on the issue with respect to the need for additional food supplies. Further, it has been widely noted that there are those who consider over-population the real issue here, and that food production is adequate for any reasonable population size.

“Genetic modification is analogous to nuclear power: nobody loves it, but climate change has made its adoption imperative,” says economist Paul Collier of Oxford University. "Declining genetic modification makes a complicated issue more complex. Genetic modification offers both faster crop adaptation and a biological, rather than chemical, approach to yield increases."

On the other hand, many believe that GM food has not been a success and that we should devote our efforts and money into another solution. “We need biodiversity intensification that works with nature’s nutrient and water cycles, not against them,” says Vandana Shiva. Shiva, the founder of Navdanya, the movement of 500,000 seed keepers and organic farmers in India, argues that GMF’s have not increased yields. Recently, Doug Gurian-Sherman, a member of the Union of Concerned Scientists, a nonprofit science advocacy group, published a report called “Failure to Yield”, in which he stated that in a nearly 20 year record, genetically engineered crops have not increased yields substantially of food and livestock feed crops in the United States.

Some claim that genetically modified food help farmers produce, despite the odds or any environmental barriers. “While new technology must be tested before it is commercially released, we should be mindful of the risks of not releasing it at all,” says Per Pinstrup-Andersen, professor of Food, Nutrition and Public Policy at Cornell University. Per Pinstrup-Anderson argues, “Misguided anti-science ideology and failure by governments to prioritize agricultural and rural development in developing countries brought us the food crisis.” He clearly states the challenge we face is not the challenge of whether we have enough resources to produce, but whether we will change our behavior.

Economic and environmental 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 nations.

The United States has seen a widespread adoption of genetically-engineered corn, cotton and soybean crops since 1996 (see figure).

In 2010, the U.S. National Academy of Sciences reported that genetically engineered crops had resulted in reduced pesticide application and reduced soil erosion from tilling. The report also stated that the advent of glyphosate-herbicide resistant weeds—that have developed because of the use of engineered crops—has had substantial negative impacts.

In a study by Scientists at the University of Arkansas published in 2010 showed that about 83 percent of wild or weedy canola they tested contained genetically modified herbicide resistance genes, and they also found some plants that contained resistance to both herbicides, a combination of transgenic traits that had not been developed in canola crops. That leads us to believe that these wild populations that contain modified genes have become established populations. Bans

In 2002, 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."

In April 2004 Hugo Chávez announced a total ban on genetically modified seeds in Venezuela.

In 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 conventional crops.

On February 9, 2010, Indian Environment Minister, Jairam Ramesh, imposed a moratorium on the cultivation of GMF "for as long as it is needed to establish public trust and confidence". His decision was made after protest from several groups responding to regulatory approval of the cultivation of Bt brinjal, a GM eggplant in October, 2009.

Intellectual property

Traditionally, farmers in all nations saved their own seed from year to year. Allowing to follow this practice with genetically modified seed would result in seed developers losing the ability to profit from their breeding work[citation needed]. 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.

Main article: Monsanto Canada Inc. v. Schmeiser

Enforcement of patents on genetically modified plants is often contentious, especially because of gene flow. 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 poles.

Although unable to prove direct theft, Monsanto sued Schmeiser for piracy since he knowingly grew Roundup Ready plants 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 cells, 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 developments

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 as researchers 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 crops.

Health risks

In the United States, the FDA Center for Food Safety and Applied Nutrition reviews summaries of food safety data developed and voluntarily submitted by developers of engineered foods, in part on the basis of comparability to conventionally-produced foods. There are no specific tests required by FDA to determine safety. FDA does not approve the safety of engineered foods[citation needed], but after its review, acknowledges that the developer of the food has asserted that it is safe. The table below shows the foods that have been reviewed by FDA as of 2002.

A 2008 review published by the Royal Society of Medicine noted that GM foods have been eaten by millions of people worldwide for over 15 years, with no reports of ill effects. Similarly a 2004 report from the US National Academies of Sciences stated: "To date, no adverse health effects attributed to genetic engineering have been documented in the human population." There have, however, been no epidemiological studies to determine whether engineered crops have caused any harm to the public. Without such studies, it is unlikely that harm, if it occurred, would be detected or attributed to engineered foods.[citation needed] Worldwide, there are a range of perspectives within non-governmental organizations on the safety of GM foods. For example, the US pro-GM pressure group AgBioWorld has argued that GM foods have been proven safe, while other pressure groups and consumer rights groups, such as the Organic Consumers Association, and Greenpeace claim the long term health risks which GM could pose, or the environmental risks associated with GM, have not yet been adequately investigated.

In 1998 Rowett Research Institute scientist Árpád Pusztai reported that consumption of potatoes genetically modified to contain lectin had adverse 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. The experiment modified potatoes to add a toxin (snowdrop lectin), but the experiment failed to include a control for the toxin alone or a control for genetic modifications alone (without added toxin); therefore, no conclusion could be made about the safety of the genetic engineering. The experiment has been criticised by other scientists on the grounds that the unmodified potatoes were not a fair control diet and that all the rats may have been sick, due to them being fed a diet of only potatoes.

In 2010 three scientists published a statistical re-analysis of three feeding trials that had previously been published by others as establishing the safety of genetically modified corn. The new article claimed that their statistics instead showed that the three patented crops (Mon 810, Mon 863, and NK 603) developed and owned by Monsanto cause liver, kidney, and heart damage in mammals. A previous re-analysis of part of this data by the same group of scientists was assessed by a panel of independent toxicologists in a study funded by Monsanto and published in the journal Food and chemical toxicology, the reviewers reported that the study was statistically flawed and providing no evidence of adverse effects.

Gene transfer

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 previously had their large intestines removed. These volunteers were to eat GM soy to see if the DNA of the GM soy transferred to the bacteria that naturally lives in the human gut. Researchers identified that three of the seven volunteers had transgenes from GM soya transferred into the bacteria living in their gut before the start of the feeding experiment. As this low-frequency transfer did not increase after the consumption of GM Soya, the researchers concluded that gene transfer did not occur during the experiment. In volunteers with complete digestive tracts, the transgene did not survive passage through intact gastrointestinal tract. Anti-GM advocates believe the study should prompt additional testing to determine its significance. Other studies have found DNA from M13 virus, GFP and even ribulose-1,5-bisphosphate carboxylase (Rubisco) genes in the blood and tissue of ingesting animals.

Two studies on the possible effects of feeding genetically modified feeds to animals found that there was no significant differences in the safety and nutritional value of feedstuffs containing material derived from genetically modified plants. Specifically, the studies noted that no residues of recombinant DNA or novel proteins have been found in any organ or tissue samples obtained from animals fed with GMP plants.

Allergies

In the mid 1990s Pioneer Hi-Bred tested the allergenicity of a transgenic soybean that expressed a Brazil nut 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 allergen.

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