Genetically Modified Foods



Genetically modified (GM) foods are food items that have had their DNA changed through genetic engineering. Unlike conventional genetic modification that is carried out through conventional breeding and that have been consumed for thousands of years, GM foods were first put on the market in the early 1990s. The most common modified foods are derived from plants: soybean, corn, canola, and cotton seed oil. For example, a typical GM Food could be a strawberry that has to survive in cold climates. Therefore, the farmer would get its DNA altered so it could survive in the frost. They would take DNA from a frost resistant cell, and transfer it into the strawberry cells genes. Therefore, the cells of the strawberry are now frost resistant and will survive the frost, so the farmer does not lose money.

Many major controversies surround genetically engineered crops and foods. These commonly focus on the long-term health effects for anyone eating them, environmental safety, labeling and consumer choice, intellectual property rights, ethics, food security, poverty reduction, environmental conservation, and potential disruption or even possible destruction of the food chain. The multi-national corporations and governments engaged in the genetic engineering of food claim the technology to be a boon for the human race, while many health-conscious people believe it to be a potential and/or actual disaster.




Development

The first commercially grown genetically modified whole food crop was the tomato (called Flavr Savr), which was made more resistant to rotting by Californian company Calgene. Calgene was allowed to release the tomatoes into the market in 1994 without any special labeling. It was welcomed by consumers who purchased the fruit at two to five times 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. However with news that Dr. Arpad Pusztai a leading UK scientist who had been hired by the Rowett Institute to develop the new safety protocol for genetically modified foods in Europe. He found that the rats in his study had developed potentially precancerous cell growth in the digestive tract, inhibited development of their brains, livers, and testicles, partial atrophy of the liver, enlarged pancreases and intestine, and immune system damage. He concluded that it was not the insecticide gene that was inserted, but was the process of genetic engineering itself.

Upon appearing on television where he said he expressed his concerns that the government and companies were using the population as Guinea pigs. Europeans were outraged, and within a week every major food company on the continent including McDonalds, Nestle and Burger King, all committed to not purchase GM foods. To date this remains one of the best designed and carefully controlled feeding studies of genetically engineered foods on mammals. The attitude towards GM foods only got worse after outbreaks of Mad Cow Disease weakened consumer trust in government regulators, and protesters rallied against the introduction of Monsanto's "Roundup Ready" soybeans.

The next GM crops included insect-resistant cotton and herbicide-tolerant soybeans both of which were commercially released in 1996. GM crops have been widely adopted in the United States. They have also been extensively planted in several other countries (Argentina, Brazil, South Africa, India, and China) where the agriculture is a major part of the total economy. Other GM crops include insect-resistant maize and herbicide-tolerant maize, cotton, and rapeseed varieties.




Growing GM Crops

Between 1995 and 2005, the total surface area of land cultivated with GMOs had increased by a factor of 50. 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 2005 the largest increase in crop area planted to GM crops (soybeans) was in Brazil.

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.) It is predicted that in 2008/9 32,000 km2 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 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 consumers.

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 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.

However, several studies have found that genetically modified varieties of plants do not produce higher yields than normal plants.




Coexistence and Traceability

In many parts of the world such as the European Union, Japan, Malaysia and Australia consumers demand labeling so they 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 impossible, reason why GM opponents use the 'genie out of a bottle' analogy.

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.

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.

The GM food controversy is a dispute over the advantages and disadvantages of genetically modified food crops.




Debate Around the World

Many scientists 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, so people should not be offered food that may carry some degree of risk.

Genetic modifications often have significant unforeseen consequences, both in the initially modified organisms and their environments. For example, certain strains of maize have been developed that are toxic to plant eating insects (see Bt corn). It has been alleged those strains cross-pollinated with other varieties of wild and domestic maize and passed on these genes with a putative impact on Maize biodiversity.

Subsequent to the publication of these results, several scientists pointed out that the conclusions were based on experiments with design flaws. It is well known that the results from polymerase chain reaction (PCR) methods of analysing DNA can often be confounded by sample contamination and experimental artifacts. Appropriate controls can be included in experiments to eliminate these as a possible explanation of the results - however these controls were not included in the methods used by Quist and Chapela.

After this criticism Nature, the scientific journal where this data was originally published concluded that "the evidence available is not sufficient to justify the publication of the original paper". More recent attempts to replicate the original studies have concluded that genetically modified corn is absent from southern Mexico in 2003 and 2004.

Also in dispute is the impact on biodiversity of the introgression of transgenes into wild populations. Unless a transgene offers a massive selective advantage in a wild population, a transgene that enters such a population will be maintained at a low gene frequency. In such situations it can be argued that such an introgression actually increases biodiversity rather than lowers it.

Activists and many scientists opposed to genetic engineering say that with current recombinant technology there is no way to ensure that genetically modified organisms will remain under control, and the use of this technology outside secure laboratory environments represents multiple unacceptable risks to both farmed and wild ecosystems.

Potential impact on biodiversity may occur if herbicide-tolerant crops are sprayed with herbicide to the extent that no wild plants ('weeds') are able to survive. Plants toxic to insects may mean insect-free crops. This could result in declines in other wildlife (e.g. birds) which feed on weed seeds and/or insects for food resources. The recent (2003) farm scale studies in the UK found this to be the case with GM sugar beet and GM rapeseed, but not with GM maize (though in the last instance, the non-GM comparison maize crop had also been treated with environmentally-damaging pesticides subsequently (2004) withdrawn from use in the EU).

Although some scientists have claimed that selective breeding is a form of genetic engineering, (e.g., maize was modified from teosinte, dogs have evolved with human intervention over the course of tens of thousands of years from wolves), others assert that modern transgenesis-based genetic engineering is capable of delivering changes faster than, and sometimes of different types from, traditional breeding methods.

Proponents of current genetic techniques as applied to food plants cite hypothetical benefits that the technology may have, for example, in the harsh agricultural conditions of Africa. They say that with modifications, existing crops could possibly be able to thrive under the relatively hostile conditions providing much needed food to their people. Proponents also cite golden rice and golden rice 2, genetically engineered rice varieties (still under development) that contain genetically-modified elevated vitamin A levels. Some hope that this rice may alleviate vitamin A deficiency that contributes to the death of millions and permanent blindness of 500,000 annually.

Proponents claim that genetically-engineered crops, although patented for economic benefit, are not significantly different from those modified by nature or humans in the past. They also argue that modified crops are as safe, or even safer, than those created through such time-tested methods. There is gene transfer between unicellular eukaryotes and prokaryotes. They argue that animal husbandry, Food Irradiation and crop breeding are also forms of genetic engineering that use artificial selection instead of modern genetic modification techniques. It is politics, they argue, not economics or science, that causes their work to be closely investigated, and for different standards to apply to it than those applied to other forms of agricultural technology.

Proponents also believe the technology could possibly prove harmless because species or genetic barriers have been crossed in nature in the past, sometimes utilizing other better time-tested and natural methods. An oft-cited example is today's modern red wheat variety, which is the result of two natural crossings made long ago. It is made up of three groups of seven chromosomes. Each of those three groups came from a different wild wheat grass. First, a cross between two of the grasses occurred, creating the durum wheats, which were the commercial grains of the first civilizations up through the Roman Republic. Then a cross occurred between that 14-chromosome durum wheat and another wild grass to create what became modern red wheat at the time of the Roman Empire.




Economic and Political Effects

Some opponents of current genetic engineering realize that increasing use of GM in major crops has caused a major power shift in agriculture towards Biotechnology companies, which are gaining more control over the production chain of crops and food, and over the farmers that use their products, as well.

Many proponents of some current genetic engineering techniques claim that it will lower pesticide usage and has brought higher yields and profitability to many farmers, including those in developing nations. A few genetic engineering licenses allow farmers in less economically developed countries to save seeds for next year's planting.

In 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."

In April 2004 Hugo Chavez 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, although these were agreed 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.The U.S. government has since declared the rice safe for human consumption, and exports to some countries have since resumed, but in the past years more crops have started to cross-pollinate which leaves a problem that is yet to be solved.




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, 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.


Genetically Modified Foods Wikipedia

Genetically Modified Foods Controversies Wikipedia





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