Genetically modified foods (GM foods or GMO foods) are foods derived from genetically modified organisms (GMOs). Genetically modified organisms have had specific changes introduced into their DNA by genetic engineering techniques. These techniques are much more precise[1] 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 1996. Typically, genetically modified foods are transgenic plant products: soybean, corn, canola, rice, and cotton seed oil. Animal products have also been developed, although as of July 2010 none are currently on the market.[2] In 2006 a pig was controversially[3][4] engineered to produce omega-3 fatty acids through the expression of a roundworm gene.[5] 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%.[6]
Critics have objected to GM foods on several grounds, including safety issues,[7] ecological concerns, and economic concerns raised by the fact these organisms are subject to intellectual property law.
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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 transferring genes as part of an attenuated virus genome or physically inserting the extra DNA into the nucleus of the intended host using a microsyringe, or as a coating on gold nanoparticles 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.
The method to introduce new genes into plants requires several important factors such as specific promoter, codon usage of the gene and how to deactivate the gene. The specific promoter must pertain to area that we want the gene to express. For instance, if we want the gene to express only in the rice instead of the leaf than we would only use an endosperm specific promoter. The reason is because we only want our transgenic genes to express only in the rice and not the leaves. The codon usage of the gene must also be more optimize for the rice since there are several different codons for each of the 20 amino acid. The transgenic genes should also be able to be denatured by heat in order for human consumption.
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.[8] Calgene took the initiative to obtain FDA approval for its release in 1994 without any special labeling, although legally no such approval was required.[9] It was welcomed by consumers who purchased them at a substantial premium over the price of regular tomatoes. However, production problems[8] 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.[10][11] 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).[12][13][14][15][16][17]
| Food | Properties of the genetically modified variety | Modification | Percent Modified in US | Percent Modified in world |
|---|---|---|---|---|
| Soybeans | Resistant to glyphosate or glufosinate herbicides | Herbicide resistant gene taken from bacteria inserted into soybean | 93% | 77% |
| Corn, field (Maize) | Resistant to glyphosate or glufosinate herbicides. Insect resistance via producing 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.[18] | New genes, some from the bacterium Bacillus thuringiensis, added/transferred into plant genome. | 86% | 26% |
| Cotton (cottonseed oil) | Pest-resistant cotton | Bt crystal protein gene added/transferred into plant genome | 93% | 49% |
| Alfalfa | Resistant to glyphosate or glufosinate herbicides | New genes added/transferred into plant genome. | Planted in the US from 2005–2007; banned until January 2011 and presently deregulated | |
| Hawaiian papaya | Variety is resistant to the papaya ringspot virus.[19] | New gene added/transferred into plant genome | 80% | |
| Tomatoes | Variety in which the production of the enzyme polygalacturonase (PG) is suppressed, retarding fruit softening after harvesting.[20] | A reverse copy (an antisense gene) of the gene responsible for the production of PG enzyme added into plant genome | Taken off the market due to commercial failure. | Small quantities grown in China |
| Canola | Resistance to herbicides (glyphosate or glufosinate), high laurate canola[21] | New genes added/transferred into plant genome | 93% | 21% |
| Sugar cane | Resistance to certain pesticides, high sucrose content. | New genes added/transferred into plant genome | ||
| Sugar beet | Resistance to glyphosate, glufosinate herbicides | New genes added/transferred into plant genome | 95% (2010); planting in 2011 under controlled conditions | 9% |
| Rice | Golden Rice: genetically modified to contain beta-carotene (a source of vitamin A) | Current version of Golden Rice under development contains genes from maize and a common soil microorganism.[22] Previous prototype version contained three new genes: two from daffodils and the third from a bacterium | Forecast to be on the market in 2013[23] | |
| Squash (Zucchini) | Resistance to watermelon, cucumber and zucchini yellow mosaic viruses[24][25] | Contains coat protein genes of viruses. | 13% | |
| Sweet Peppers | Resistance to virus[26] | Contains coat protein genes of the virus. | Small quantities grown in China |
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.[27]
Between 1997 and 2010, the total surface area of land cultivated with GMOs had increased by a factor of 87, from 17,000 km2 (4.2 million acres) to 1,480,000 km2 (365 million acres). 10% of the world's crop lands were planted with GM crops in 2010.[28]
Although most GM crops are grown in North America, in recent years there has been rapid growth in the area sown in developing countries. A total of 29 countries worldwide grew GM crops in 2010 by approximately 15.4 million farmers.[29] In 2010, 48% of GM crops grown worldwide were grown in developing countries. For example, the largest increase in crop area planted to GM crops (soybeans) in 2010 was in Brazil (254,000 km2 versus 214,000 km2 in 2009). 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) with 94,000 km2 of GM cotton harvested in India in 2010.[28]
In India, GM cotton yields in Andhra Pradesh were no better than non-GM cotton in 2002, the first year of commercial GM cotton planting. This was because there was a severe drought in Andhra Pradesh that year and the parental cotton plant used in the genetic engineered variant was not well suited to extreme drought. Maharashtra, Karnataka, and Tamil Nadu had an average 42% increase in yield with GM cotton in the same year.[30] Drought resistant variants were developed and, with the substantially reduced losses to insect predation, by 2009 87% of Indian cotton was GM.[14] Though disputed[31][32] the economic and environmental benefits of GM cotton in India to the individual farmer have been documented.[33][34]
In 2010, countries that grew the most transgenic crops were the United States (45%), Brazil (17%), Argentina (15%), India (6%), Canada (6%), China (2%), Paraguay (2%), Pakistan (2%), South Africa (1%) and Uruguay (1%).[28] The Grocery Manufacturers of America estimated in 2003 that 75% of all processed foods in the U.S. contain a GM ingredient.[35] 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, may 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.[12][13] 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.[36]
In 2005, after completing a 28-page Environmental Assessment (EA)[37] the United States Department of Agriculture (USDA) granted Roundup Ready Alfalfa (RRA) nonregulated status.[38] In 2006, the Center for Food Safety (and others) challenged this deregulation in the California Northern District Court[39] The District Court ruled that the USDA's EA did not address two issues concerning RRA's effect on the environment [40] and in 2007, required the USDA to complete a much more extensive Environmental Impact Statement (EIS). Until the EIS was completed, they banned further planting of RRA.[41] The USDA proposed a partial deregulation of RRA but this was also rejected by the District Court.[39] Planting of RRA was halted. Monsanto (and others) appealed in 2010 to the US Supreme Court. In June 2010, the Supreme Court upheld the ruling of the District Court that the USDA was required to complete an EIS before deregulating RRA. However the Supreme Court overturned the District Court decision to ban planting RRA nationwide as there was no evidence of irreparable injury. They ruled that the USDA could partially deregulate RRA before an EIS was completed.[39] The USDA chose not to allow partial deregulation as the EIS was almost complete. Their 2,300 page EIS was published in December 2010.[42] It concluded that RRA would not affect the environment. After a comment period the USDA deregulated RRA in January 2011 and planting resumed.[43] A new lawsuit by the Center for Food Safety (and others) to stop further development of Roundup Ready alfalfa was filed against USDA in March 2011.[44]
Between 2009 and 2011, the United States District Court for the Northern District of California considered the case involving the planting of genetically modified sugar beets.[45] This case involves Monsanto's breed of pesticide-resistant sugar beets.[46] 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. On 13 August 2010, Judge White ordered a 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 organization that is a critic of biotech crops.[47] On the 25th February 2011, a federal appeals court for the Northern district of California in San Francisco overturned a previous ruling by Judge Jeffrey S. White to destroy juvenile GM sugar beets, ruling in favor of Monsanto, the Department of Agriculture’s Animal and Plant Health Inspection Service (APHIS) and four seed companies. The court concluded that " The Plaintiffs have failed to show a likelihood of irreparable injury. Biology, geography, field experience, and permit restrictions make irreparable injury unlikely." [48] In February 2011, The USDA allowed commercial planting of GM sugar beet under closely controlled conditions.[49][50]
A 1999 study by Charles Benbrook, Chief Scientist of the Organic Center,[51] found that genetically engineered Roundup Ready soybeans did not increase yields.[52] The report reviewed over 8,200 university trials in 1998 and found that Roundup Ready soybeans had a yield drag of 5.3% across all varieties tested. In addition, the same study found that farmers used 2–5 times more herbicide (Roundup) on Roundup Ready soybeans compared to other popular weed management systems.[53]
However research published in Science in 2003 has shown that the use of genetically modified Bt cotton in India increased yields by 60% over the period 1998–2001 while the number of applications of insecticides against bollworm were three times less on average.[54]
A 2008 Soil Association report found that some scientific studies claimed that genetically modified varieties of plants do not produce higher crop yields than normal plants.[55]
In 2009 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 (corn).[56] 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.
A 2010 article supported by CropLife International summarised the results of 49 peer reviewed studies on GM crops worldwide.[57][58] On average, farmers in developed countries experienced increase in yield of 6% and in underdeveloped countries of 29%. Tillage was decreased by 25–58% on herbicide resistant soybeans, insecticide applications on Bt crops were reduced by 14–76% and 72% of farmers worldwide experienced positive economic results.
The United States and Canada do not require labeling of genetically modified foods.[59] 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.[60][61] 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.[60][61]
For traceability, the OECD has introduced a "unique identifier" which is given to any GMO when it is approved.[62] This unique identifier 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 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,[63] 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.
A 5-digit Price Look-Up code beginning with the digit 8 indicates genetically modified food;[64] however the absence of the digit does not necessarily indicate the food is not genetically modified.
While it is evident that there is a food supply issue,[65][66][67] 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.[68] 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.[69][70] Recently some critics and environmentalists have changed their minds on the issue with respect to the need for additional food supplies.[71][72][73] 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."[74]
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, the founder of Navdanya, the movement of 500,000 seed keepers and organic farmers in India, argues that GMFs 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.[75]
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-Andersen 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.[76]
In March 2011 a coalition of family farmers, consumers and other critics of corporate agriculture held a town meeting to protest what they see as unfair consolidation of the nation's food system into the hands of a few multinationals. They contend that global biotech seed leader Monsanto controls the U.S. commercial seed market using unfair, and in some cases illegal, practices. They argue that Monsanto, which develops, licenses and markets genetically altered corn, soybeans and other crops, manipulates the seed market by buying up independent seed companies, patenting seed products, and then spiking prices. The group hopes to re-establish farmer rights to save seed from their harvested crops and replant it.[77][78]
In recent years, France and several other European countries banned Monsanto's MON-810 corn and similar genetically modified food crops. In late 2007, the U.S. ambassador to France recommended "moving to retaliation" against France and the European Union in an attempt to fight the French ban and changes in European policy toward genetically modified crops, according to a U.S. government diplomatic cable obtained by WikiLeaks. The U.S. ambassador to France recommended retaliation to cause "some pain across the EU."[96][97]
Traditionally, farmers in all nations saved their own seed from year to year. It should be noted that this does not apply in more agriculturally developed countries for some crops. Corn is one example where producers generally have not saved seed since the early 1900s with the advent of hybrid corn through selective breeding. Seed producers grow the seed corn instead due to the effort needed to produce hybrids.[98] The offspring of the hybrid corn, while still viable, lose the beneficial traits of the parents, resulting in the loss of hybrid vigor. In these cases, the use of hybrid plants has been the primary reason for growers not saving seed, not intellectual property issues, and has been in practice well before genetically-modified seed was developed. However, the practice of not saving seed in non-hybrid crops, such as soybean, is mainly due to intellectual property regulations. Allowing 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 is subject to licensing by their developers in contracts that are written to prevent farmers from following this practice.[99]
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.[100] 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 found 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.[101]
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.[100][101] 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."[102]
Future envisaged applications of GMOs are diverse and include drugs in food, bananas that produce human vaccines against infectious diseases such as Hepatitis B,[103] 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.[104] 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.[105][106]
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, 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.[107]
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.[108] 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."[7] The European Commission Directorate-General for Research and Innovation 2010 report on GMOs noted that "The main conclusion to be drawn from the efforts of more than 130 research projects, covering a period of more than 25 years of research, and involving more than 500 independent research groups, is that biotechnology, and in particular GMOs, are not per se more risky than e.g. conventional plant breeding technologies."[109]
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. 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,[110] while other pressure groups and consumer rights groups, such as the Organic Consumers Association,[111] and Greenpeace[112] 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.[113] Pusztai eventually published a letter, co-authored by Stanley Ewen, in the journal, The Lancet. The letter 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.[114] 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 their being fed a diet of only potatoes.[115]
In 2009 three scientists (Vendômois et al.) published a statistical re-analysis of three feeding trials that had previously been published by others as establishing the safety of genetically modified corn.[116][117][118] 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.[119] A 2007 analysis of part of this data by the same group of scientists funded by Greenpeace[120] was assessed by a panel of independent toxicologists in a study funded by Monsanto and published in the journal Food and chemical toxicology. Some reviewers reported that the study was statistically flawed and providing no evidence of adverse effects.[121] The French High Council of Biotechnologies Scientific Committee reviewed the 2009 Vendômois et al. study and concluded that it "..presents no admissible scientific element likely to ascribe any haematological, hepatic or renal toxicity to the three re-analysed GMOs."[122][123] An evaluation by the European Food Safety Authority of the 2009 and 2007 studies noted that most of the results were within natural variation and they did not consider any of the effects reported biologically relevant.[124][125] A review by Food Standards Australia New Zealand of the 2009 Vendômois et al. study concluded that the results were due to chance alone.[126]
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 Soy, 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.[127] Anti-GM advocates believe the study should prompt additional testing to determine its significance.[128] 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.[129][130]
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.[131][132] 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.
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.[133] Pioneer has indicated that it will not develop commercial cultivars containing Brazil nut protein because the protein is likely to be an allergen.[134]
A 2011 study, the first to evaluate the correlation between maternal and fetal exposure to pesticides associated with genetically modified foods and to determine exposure levels of the pesticides and their metabolites, revealed the presence of pesticides associated with GM foods in both non-pregnant women and pregnant women and their fetuses.[135] However the study has been found to be unconvincing by several authors[136][137] as well as by Food Standards Australia New Zealand.[138]
In a January 2010 paper[139] the extraction and detection of DNA along a complete industrial soybean oil processing chain was described to monitor the presence of Roundup Ready (RR) soybean: "The amplification of soybean lectin gene by end-point polymerase chain reaction (PCR) was successfully achieved in all the steps of extraction and refining processes, until the fully refined soybean oil. The amplification of RR soybean by PCR assays using event-specific primers was also achieved for all the extraction and refining steps, except for the intermediate steps of refining (neutralisation, washing and bleaching) possibly due to sample instability. The real-time PCR assays using specific probes confirmed all the results and proved that it is possible to detect and quantify genetically modified organisms in the fully refined soybean oil. To our knowledge, this has never been reported before and represents an important accomplishment regarding the traceability of genetically modified organisms in refined oils."
Pros and Cons of GM food.
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