It also lays the ground-work for deep debate on benefits and risks of Biotech-crops for human health, ecosystems and biodiversity. In this context, although some regulations exist, there is a need for continuous vigilance for all countries involved in producing genetically engineered food to follow the international scientific bio-safety testing guidelines containing reliable pre-release experiments and post-release track of transgenic plants to protect public health and avoid future environmental harm.
Genetically Modified Organisms GMOs are being made by inserting a gene from an external source such as viruses, bacteria, animals or plants into usually unrelated species.
Biotechnology has granted us the ability to overcome insurmountable physiological barriers and to exchange genetic materials among all living organisms. The use of recombinant DNA technology has the potential to allow the creation of an organism which is desired and designed by human. Genetically Modified Food GMF means any food containing or derived from a genetically engineered organism 1.
Describing biotechnology methods is beyond the scope of this paper however, it is informative to only name some of the vastly used techniques in creating GM crops: Agrobacterium has been used as an intermediate organism for transferring a desirable gene into plants 2. This has been a successful method for modification of trees and cereal crops. Biolistic transformation is a physical method by which the genes of interest are bombarded into the plant cells and DNA-coated beads are usually used as carriers 3.
Another technique which facilitates the in-corporation of genes into the host genome is called Electroporation.
This is a suitable method for plant tissues without cell walls. DNA enters the plant cells through minute pores which are temporarily caused by electric pulses 4. These holes can be also created by microscopic crystals. Another recent method consists of Microinjection which is direct introduction of DNA into genome 5. Antisense technology is also a useful method for deactivation of specific genes such as those responsible for softening of fruits and fighting against plant viral infections 6.
With currently available techniques the favorite DNA are inserted to only a few numbers of the treated cells. Therefore, in order to detect whether the incorporation of the gene to the cell has taken place, the desired DNA are generally attached to marker gene before their transfer.
These marker genes allow researchers to verify whether transfer of the desired DNA has properly occurred. However, after the successful gene transfer, important factors that have triggered debates over the safety of GM crops are the genotypic and phenotypic stability and permanence inheritance 7.
The majority of the Biotech-crops available on the global market have been genetically manipulated to express one of these basic traits: resistance to insects or viruses, tolerance to certain herbicides and nutritionally enhanced quality.
At present, more than million hectares of farmland are under cultivation for biotech crops throughout the world 8. There has been a fold rise in the application of Agri-biotechnology since , when the first biotech-crop was commercially produced 9. Developing countries are rapidly accepting the technology with the hope of alleviating hunger and poverty.
It is predicted that, by , more than million hectares of lands will be planted by biotech crops in about 40 countries 9. The emergence of agricultural biotechnology has created social and ethical contradictions. The widespread debate exists as to how biotechnology can be used for planting high quality high yield crops while protecting eco-system and human health. While it is claimed that food biotechnology, by improvement of the plant productivity and developing nutrient-fortified staple food, is the promising solution to malnutrition and food shortage, the accumulating evidence over 20 years of GMF introduction to the market does not fully support these claims.
The consumers are mainly concerned about the long term human health effects of the bio-tech crops such as antibiotic resistance, aller-genicity, unnatural nutritional changes and toxicity.
Furthermore, Agri-biotech companies and their affiliated scientists present GM food as an environmentally friendly crop. It is excessively stated over the media and through their dependent scientific publications that GM crops containing genes expressing herbicide tolerance and pest resistance lead to reduction of broad spectrum pesticides and herbicide use. Also, they profess that GM crops help diminishing greenhouse global emissions by reducing needs for plowing replacement of energy-intensive by low-till agriculture.
On the other hand, environmentalists believe that engineering of the genetic materials could deeply transform the global ecosystem from all possible aspects They are concerned about the long term consequences of GM agriculture on biodiversity as it may create superweeds and superpests which can potentially disturb the balance of nature and cause serious hazards for beneficial insects. In this article, different views on agricultural biotechnology which has given rise to debates between advocated and opponents of GM crop are provided.
The information presented in this review was collected through extensive web searches of databases such as Regulatory Framework on Food Biosafety implemented by UNEP-GEF; guidelines of European Parliament's committee on the Environment, Public Health and Food Safety; Food and Agriculture Organization of the United Nations, biosafety guidelines for crop production and food labeling and also scientific data presented by independent scientists of non-profit international organizations and many others.
Much of the current debates on agricultural biotechnology have focused on the potential risks of GM crops for human health. Some of the health risks pertinent to unapproved GMFs include antibiotic resistance, aller-genicity, nutritional changes and the formation of toxins To address the possible drawbacks of biotechnology application in engineered foods, we point out some of the problems stemming out from genetic modification techniques.
GE techniques have been used to transfer single gene traits such as herbicide tolerance from soil microbes into plant cells. However, recent studies in higher eukaryotic cells have shown that genes do not function independently from each other. For example, it has been discovered that human genome is not a simple collection of independent genes. Genes, instead of being constant and static, are dynamic and operate in an interactive system and intertwined with one another.
Furthermore, proteins do not function separately; rather they behave in interactive network systems. Gene traits work in the cell by inter-communication and reciprocity Hence, one gene might not determine one trait, be it herbicide tolerance, or resistance to pest. Therefore, the genetic engineering techniques seem to be imprecise and must include gene optimization steps to minimize this concern.
The new understanding of genome function has changed the genetic concept which launched biotech industry a couple of decades ago To make a GM crop, the gene of interest is inserted into the crop's genome using a vector. This vector might contain several other elements, including viral promoters, transcription terminators, antibiotic resistance and marker genes.
The genes incorporated into a genome, could reside anywhere, cause mutation in the host genome, and move or rear-range after insertion or in the next generations. Transgenic DNA might break up and reintegrate into the genome again recombination leading to chromosomal rearrangement in successive generations and could potentially change the transgenic crops in a way to produce proteins that are allergic or cause other health problems 17 , As DNA does not always fully defragment in the digestive system, human gut microflora and pathogens can take up GM materials including antibiotic resistance genes This may cause the reduction of the effectiveness of antibiotics and therefore increasing the risk of antibiotic-resistant diseases.
Some scientific advices have proposed that such markers should be replaced by non-antibiotic marker system in GMF production However, the proponent of commercial production of GMF believe that DNA are abundant in all the foods we eat, but there has not been any evidence of the gene transfer from the food source to gut bacteria. However, there is a concern that the existence of viral promoters in the vectors carrying the foreign genes might expose the consumer to the viral infection.
It is of concern that this promoter could potentially becomes activated in human and animal cells 22 , Seed companies argue that viruses have been engineered to be dormant in plant cells and therefore they are safe. Contrary to these claims, studies have shown that viruses, lacking the gene needed for movement, can easily gain it from neighboring genes 24 , Many scientific data indicate that animals fed by GM crops have been harmed or even died.
Rats exposed to transgenic potatoes or soya had abnormal young sperm; cows, goats, buffalo, pigs and other livestock grazing on Bt-maize, GM cottonseed and certain biotech corn showed complications including early deliveries, abortions, infertility and also many died 26 — However, this is a controversial subject as studies conducted by company producing the biotech crops did not show any negative effects of GM crops on mice Although Agri-biotech companies do not accept the direct link between the GMFs consumption and human health problems, there are some examples given by the opponents.
There are also reports on hundreds of villagers and cotton handlers who developed skin allergy in India 34 , Recent studies have revealed that Bacillus thuringiensis corn expresses an allergenic protein which alters overall immunological reactions in the body 36 , The aforementioned reports performed by independent GM researchers have lead to a concern about the risks of GMFs and the inherent risks associated with the genetic technology.
It is therefore essential that the safety and long-term effects of GM crops should be examined before their release into the food chain by all organizations responsible to produce GMFs. In order to give the public the option of making informed decision about the consumption of GMF, enough information on the safety tests of such product is required. Unfortunately, such data are scarce due to a number of factors.
For example it is hard to compare the nutritional contents of GM crops with their conventional counterparts because the composition of crops grown in different areas might vary depending on the growth and agronomic conditions. At the present there is no peer-reviewed publication on clinical studies of GMF effects on human health. Current testing methods being used in bio-tech companies appear to be inadequate. For instance, only chemical analysis of some nutrients are reported and generally consider the GM crops equal to its conventional crops when no major differences are detected between the compound compositions in both products.
Such approach is argued to guarantee that the GM crop is safe enough to be patented and commercially produced 38 , It is strongly believed that animal trials should be used to evaluate the probable toxic effects of genetically modified foods 38 , Herbicide and glyphosphate resistant soybeans 41 — 43 as well as GM cotton resistant to insects are claimed to be substantially equal to conventional soybeans or cotton However, in these studies other than the use of inappropriate statistics, instead of comparing GM crops with the control grown at same locations, samples from different areas were measured, while it is known that environmental conditions could have major effects on the components levels 41 , 44 , Another example are from the results of toxicological studies conducted on a variety of animals fed with glyphosate-resistant soybean GTS which were shown to be similar for GTS fed and control group.
However, these experiments were not scientifically sound since high dietary protein concentration and very low level of GTS have hidden any real effects of GM and basically these experiments were more a commercial and not scientific studies Also, there are some false claims on the improvement of the protein content of GM crops expressing the desired protein from an inserted gene.
For example, studies on GM potato and containing soybean glycine gene did not show considerable increase in the protein content or even amino acid profile and as for GM rice the rise in protein content was due to the decline in moisture rather than the increase in protein content 28 , Also, there are some difficulties with assessing the allergenicity of GM crops. When the gene causing allergenicity is known, such as the gene for the alpha-amylase trypsin inhibitors, or cod proteins, it is easier to recognize whether the GMF is allergenic by using in vitro tests 48 — Since insertion of a non-allergenic gene might cause over expression of already existing minor allergen, it is difficult to specifically identify whether a new GM crop with a gene transferred from a source with unknown allergenicity is allergenic before its introduction to the food chain.
In order to verify whether people have been harmed over the years by consuming GMF, specifically in countries like the US where people's dietary are mainly composed of such products, the law for mandatory labeling is highly required. We also ask whether gluten sensitivity truly exists. In this Honest Nutrition feature, we tackle the issue of funding: Who funds nutrition research, and do funding sources impact study credibility? This Honest Nutrition feature looks at the foods that allegedly 'speed up' metabolism, and it gives an overview of the science behind this claim.
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Share on Pinterest Illustration by Diego Sabogal. What are GM foods? Why create GM foods? View All. Clean eating: What does the research say? Carbohydrates: Are they really essential? How bad are carbs, really? Common GM foods. Reduce lignin. Reduce phytate. Pollination control. Resistance to insects. Increased yield Pollination control. Increased lysine essential amino acid. Bangladesh, India Cooking Papaya Resistance to viruses.
No flowering. Costa Rica Fresh fruit Potato Reduce browning. Less black spot bruising. Resistance to viruses. Altered oil profile. Increased yield. Myths and Facts. GM ingredients come from organisms that have had their genetic material altered using non-traditional breeding methods known as gene technology. Traditional methods of genetic modification have been used for centuries through conventional breeding practices such as the selective crossing of plants for preferred traits and since the s, by exposing seeds to chemicals or radiation to generate new or enhanced traits.
Today's genetic modification is a much more targeted process and can involve the transfer of genes from unrelated species. Genes used for genetic modification may come from a range of organisms, including bacteria, plant or animal species.
Gene technology, sometimes referred to as genetic engineering, is faster than traditional breeding and provides ways of introducing very precise changes to genetic material resulting in the expression of desirable traits.
These changes may involve the transfer of properties of a single gene from one organism to another. For instance, some genes may produce herbicide or insect resistance, or improve crop yields, and these can be transferred into food crops such as corn or canola.
The GM crops grown in Australia with approval from the relevant authorities are canola also known as oilseed rape and cotton. GM canola grown in Australia is resistant to certain types of herbicide. GM cotton has been modified to be resistant to certain types of cotton pests. In other countries, several other GM crops with a wide range of new properties are being grown.
New GM varieties are also currently being developed and tested nationally and internationally. For example, in Australia, GM crops are being developed to be able to withstand drought.
GM whole foods such as soy, maize or sugar beet may be used as ingredients in food. None of these GM crops are grown in Australia, but some products for sale in Australia may contain imported GM ingredients. There are currently no approved imports of fresh GM fruit or vegetables in Australia. Any application to import and sell products like this in Australia would have to go through a strict approval process. GM foods and ingredients are subject to a mandatory pre-market safety assessment by the government food regulator called Food Standards Australia New Zealand FSANZ before they enter the country and before they are used in foods for human consumption.
GM foods and ingredients are regulated in the Code under Standard 1. There are currently suspensions on the commercial growing of GM crops in South Australia and Tasmania.
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