Bacillus thuringiensis (Bt) crops are plants genetically engineered (modified) to contain the endospore (or crystal) toxins of the bacterium, Bt to be resistant to certain insect pests. In 1995, the Environmental Protection Agency (EPA) in USA approved the commercial production and distribution of the Bt crops: corn, cotton, potato, and tobacco. Currently, the most common Bt crops are corn and cotton. The crystal, referred to as Cry toxins, is proteins formed during sporulation of some Bt strains and aggregate to form crystals. Such Cry toxins are toxic to specific species of insects belongs to orders: Lepidoptera, Coleoptera, Hymenoptera, Diptera, and Nematoda. In 2016, the total world area cultivated with genetically modified crops (GM crops) reached about 185 million ha. This review shows that there is a worldwide controversy about the safety of Bt crops to the environment and mammals. Some researchers support the cultivation of Bt crops depending upon the results of their laboratory and field studies on the safety of such crops. Others, however, are against Bt crops as they may cause risk to human.
Genetically Modified Food In India Pdf Download
When a gene from one organism is transferred to improve or induce desired change in another organism, in laboratory, the result is a genetically engineered (or modified) organism (which may also called transgenic organism). There are different methods to transfer genes to animals and plants where the old and most traditional one is through the selective breeding. For example, a plant with a desired trait is selected and bred to produce more plants with such a trait. Recently, with the reached high technology, advanced techniques are carried out in laboratory to transfer genes that express the desired traits from a plant to a new plant (Martineau 2001).
The first produced genetically modified plant in the laboratory was tobacco in 1983 and was tested in 1986 as herbicide-resistant in France and the USA. In 1994, the European Union approved the commercial production of the plant as resistant to the herbicide bromoxynil (Martineau 2001).
Tomato was the first commercially grown genetically modified whole food crop (called FlavrSavr) which was modified to ripen without softening by a Californian company, Calgene (Martineau 2001). Calgene took the initiative to obtain the Food and Drug Administration (FDA) approval for its release in 1994. It was welcomed by consumers who purchased the fruit at high price. However, a conventionally bred variety with longer shelf-life prevented the product from becoming profitable.
For cotton growers, there was a lot of pressure from pests before the introduction of Bt cotton. Due to synthetic insecticide resistance, farmers were losing much of their cotton because of H. virescens and pink bollworm, Pectinophora gossypiella. According to USDA, 94% of the cotton cultured in USA is genetically modified (James 2016).
In 2004, a human feeding study was conducted to determine the effects of genetically modified (GM) food. Seven human volunteers were allowed to eat genetically modified soybean (resistant to the herbicide Roundup) to see if the DNA of GM soybean was transferred to the human gut bacteria. The examination of their guts showed that no recombinant DNA was found (Netherwood et al. 2004). However, the anti-GM crops advocates believe that the study needs additional testing to determine its significance (Smith 2007).
India has a systematic and structured regulatory framework for biosafety evaluation of genetically modified organisms (GMOs) and products thereof. India was one of the early movers in development of a biosafety regulatory system for GMOs, way back in 1989. The apex rules for regulation of all activities related to GMOs are notified under Environment (Protection) Act, 1986. In addition, there are other acts, rules and policies which are also applicable to these organisms.
Guidelines for the Safety Assessment of Foods Derived from Genetically Engineered (GE) Plants were prepared by the Indian Council of Medical Research and adopted by RCGM and GEAC in 2008 [6]. These guidelines provide guidance on principles and steps on food safety assessment of GE plants and are based on guidelines and principles of Codex Alimentarius Commission, 2003. A series of accompanying protocols were prepared by DBT [7]. The guidelines include three appendices on dossier preparation checklist, Codex Alimentarius principles for the risk analysis of foods derived from modern biotechnology, safety assessment of foods derived from GE plants modified for nutritional or health benefits and food safety assessment in situations of low level presence of GE plant material in food.
This protocol specifies the methodology for identifying, evaluating, and mapping evidence related to the main review question: what are the socio-economic impacts of genetically modified crops worldwide? This question has been subdivided into the following topics: (a) farm-level impacts; (b) impacts of coexistence regulations; (c) impacts along the supply chain; (d) consumer-level impacts; (e) impacts on food security; and (f) environmental economic impacts. The search strategy includes the identification of primary studies from general scientific databases; global, regional, and national specialist databases; an on-line search engine; institutional websites; journal websites; subject experts/researchers; and serendipity. Searches will be conducted in six languages (Chinese, English, French, German, Portuguese, and Spanish). Identified studies will be screened for inclusion/exclusion criteria by a group of multi-language reviewers. Finally, pre-defined data from the studies will be extracted, mapped, and presented in a report. Potential research gaps will be identified and discussed, and the review process will be documented in an open-access database (i.e. CADIMA, ).
Genetically modified crops (GM crops) are plants used in agriculture, the DNA of which has been modified using genetic engineering methods. Plant genomes can be engineered by physical methods or by use of Agrobacterium for the delivery of sequences hosted in T-DNA binary vectors. In most cases, the aim is to introduce a new trait to the plant which does not occur naturally in the species. Examples in food crops include resistance to certain pests, diseases, environmental conditions, reduction of spoilage, resistance to chemical treatments (e.g. resistance to a herbicide), or improving the nutrient profile of the crop. Examples in non-food crops include production of pharmaceutical agents, biofuels, and other industrially useful goods, as well as for bioremediation.[1]
Modern advances in genetics have allowed humans to more directly alter plants genetics. In 1970 Hamilton Smith's lab discovered restriction enzymes that allowed DNA to be cut at specific places, enabling scientists to isolate genes from an organism's genome.[36] DNA ligases that join broken DNA together had been discovered earlier in 1967,[37] and by combining the two technologies, it was possible to "cut and paste" DNA sequences and create recombinant DNA. Plasmids, discovered in 1952,[38] became important tools for transferring information between cells and replicating DNA sequences. In 1907 a bacterium that caused plant tumors, Agrobacterium tumefaciens, was discovered and in the early 1970s the tumor inducing agent was found to be a DNA plasmid called the Ti plasmid.[39] By removing the genes in the plasmid that caused the tumor and adding in novel genes researchers were able to infect plants with A. tumefaciens and let the bacteria insert their chosen DNA sequence into the genomes of the plants.[40] As not all plant cells were susceptible to infection by A. tumefaciens other methods were developed, including electroporation, micro-injection[41] and particle bombardment with a gene gun (invented in 1987).[42][43] In the 1980s techniques were developed to introduce isolated chloroplasts back into a plant cell that had its cell wall removed. With the introduction of the gene gun in 1987 it became possible to integrate foreign genes into a chloroplast.[44] Genetic transformation has become very efficient in some model organisms. In 2008 genetically modified seeds were produced in Arabidopsis thaliana by dipping the flowers in an Agrobacterium solution.[45] In 2013 CRISPR was first used to target modification of plant genomes.[46]
The first genetically engineered crop plant was tobacco, reported in 1983.[47] It was developed creating a chimeric gene that joined an antibiotic resistant gene to the T1 plasmid from Agrobacterium. The tobacco was infected with Agrobacterium transformed with this plasmid resulting in the chimeric gene being inserted into the plant. Through tissue culture techniques a single tobacco cell was selected that contained the gene and a new plant grown from it.[48] The first field trials of genetically engineered plants occurred in France and the US in 1986, tobacco plants were engineered to be resistant to herbicides.[49] In 1987 Plant Genetic Systems, founded by Marc Van Montagu and Jeff Schell, was the first company to genetically engineer insect-resistant plants by incorporating genes that produced insecticidal proteins from Bacillus thuringiensis (Bt) into tobacco.[50] The People's Republic of China was the first country to commercialise transgenic plants, introducing a virus-resistant tobacco in 1992.[51] In 1994 Calgene attained approval to commercially release the Flavr Savr tomato, a tomato engineered to have a longer shelf life.[52] Also in 1994, the European Union approved tobacco engineered to be resistant to the herbicide bromoxynil, making it the first genetically engineered crop commercialised in Europe.[53] In 1995 Bt Potato was approved safe by the Environmental Protection Agency, after having been approved by the FDA, making it the first pesticide producing crop to be approved in the US.[54] In 1996 a total of 35 approvals had been granted to commercially grow 8 transgenic crops and one flower crop (carnation), with 8 different traits in 6 countries plus the EU.[49] By 2010, 29 countries had planted commercialised genetically modified crops and a further 31 countries had granted regulatory approval for transgenic crops to be imported.[55] 2ff7e9595c
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