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GENETICALLY MODIFIED FOODS

Genetically modified (GM) foods are food items that have their DNA altered through genetic engineering. Unlike conventiona! genetic modification that has been carried out through conventionaf breeding for thousands of years, GM foods first appeared in the market in the early 1990s. The most common modified foods are derived from plants: soybean, com, canola, cotton seed oii and fruit. For exampie, a typical GM food could be a strawberry that has to survive under hostile weather conditions, i.e. in cold ciimate. A farmer would get its DNA changed, so that it could survive in the frost. They would take DNA from frost resistant celi, and transfer it into the strawberry genes. Popular GM crops inciude insect-resistant corn and herbicide-tolerant cotton, corn and rapeseed varieties. Lots of controversies surround genetically engineered crops and foods. One of them focuses on the long-term health effects for anyone eating them. In the late 1990s dr. Arpad Pusztai, a leading UK scientist, was hired by the Rowett Institute to develop a new safety protocol for genetically modified foods in Europę. E.g. he found that the rats used in his study had devełoped potentially precancerous celi growth in the digestive tract, which inhibited the rats¹ brain, liver and testicle development and generally weakened the immunity system. As he conciuded, it was just because insecticide gene was inserted in a rat’s gene system.

Activists and many scientists opposed to genetic engineering say that with current 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 unacceptabfe risks to both farm 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 insecłs may mean insect-free crops. However, this could result in deciine of other wiidlife (e.g.) birds which reiy on weed seeds and/or insects as food resources.

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

Proponents of current genetic techniques as applied to food plants point to hypothetical benefits that the technology may have, for examp!e, in the harsh agricultural conditions in Africa. They argue that with modifications, existing crops could possibly be able to thrive under the relatively hostile conditions providing much needed ford to malnourished people. Proponents also cite golden rice and golden rice 2, genetically engineered rice varietes that contain genetically modified vitamin A levels. Some hope this rice variety may boost vitamin A deficiency that currently claims thousands of lives every year.