Thursday, October 3, 2013

Controversies Involving Genetically Modified Foods

Controversies
The genetically modified foods controversy is a dispute over the use of food and other goods derived from genetically modified crops instead of from conventional crops, and other uses of genetic engineering in food production. The dispute involves consumers, biotechnology companies, governmental regulators, non-governmental organizations, and scientists. The key areas of controversy related to genetically modified food are: whether GM food should be labeled, the role of government regulators, the effect of GM crops on health and the environment, the effect on pesticide resistance, the impact of GM crops for farmers, and the role of GM crops in feeding the world population.

The starting point for assessing the safety of all GM food is to evaluate its substantial equivalence to the non-modified version. Further testing is then done on a case-by-case basis. Despite concerns over potential toxicity, allergenicity or gene transfer to humans from GM food, there is broad scientific consensus that food on the market derived from GM crops poses no greater risk than conventional food. There is no evidence to support the idea that the consumption of approved GM food has a detrimental effect on human health.

Although labeling of genetically modified organism (GMO) products in the marketplace is required in many countries, it is not required in the United States and no distinction between GMO and non-GMO foods is recognized. In the United States, the Food and Drug Administration does not require labeling of GMO products in the marketplace, nor does it recognize a distinction between GMO and non-GMO foods.
Some advocacy groups such as Greenpeace and the World Wildlife Fund have concerns that risks of GM food have not been adequately identified and managed, and have questioned the objectivity of regulatory authorities. Opponents of food derived from GMOs are concerned about the safety of the food itself and wish for GMOs to be banned or at least labeled on the food packages of foods they are in. They have concerns about the objectivity of regulators and rigor of the regulatory process, about contamination of the non-GM food supply, about effects of GMOs on the environment, about industrial agriculture in general, and about the consolidation of control of the food supply in companies that make and sell GMOs, especially in the developing world. Some are concerned that GM technology tampers too deeply with nature. Other environmental groups, including The Nature Conservancy and former anti-GMO campaigner Mark Lynas support the use of GMOs as beneficial for the environment.

Regulation
The regulation of genetic engineering concerns the approaches taken by governments to assess and manage the risks associated with the use of genetic engineering technology and the development and release of genetically modified organisms (GMO). There are differences in the regulation of GMOs between countries, with some of the most marked differences occurring between the USA and Europe. Regulation varies in a given country depending on the intended use of the products of the genetic engineering. For example, a crop not intended for food use is generally not reviewed by authorities responsible for food safety, while GM crops intended for use in human or animal food are reviewed by such authorities. Additionally, various govern the importation of GM commodities, as well as food made using GM commodities.

Detection
Testing on GMOs in food and feed is routinely done using molecular techniques like DNA microarrays or quantitative PCR. 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.
In a January 2010 paper, 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."

http://en.wikipedia.org/wiki/Genetically_modified_food

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