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1 GENETICALLY MODIFIED ORGANISMS AND CHALLENGES Bishnu Karki ABSTRACT Genetically modified organisms have been developed by application of advanced techniques of genetic engineering. GM crops offer distinctive advantages like insects, weed, disease and drought resistance, better nutritional value and higher yield. However in a considerable part of the world, non governmental organizations and/or the general public are hesitating or opposing the cultivation and application of GM crops. There are several environmental and public issues concerning the GMO’s.Overall, genetic engineering of the organisms, plants and animals is accepted conditionally; the gene inserted and its products should be carefully assessed both for human and environmental safety before release into the nature and to the public market. In many countries in the world, especially, those is the European Union, GM food is still considered as undesirable. Mandatory labeling is required when more than 1% of any ingredient of food which originates from the GMO. Thus, there are several research are on progress for development of the valid GMO detection method. KEY WORDS Genetically modified organism, Environmental risks assessment, herbicide resistance, Biosafety Regulations. INTRODUCTION The rapid development in biotechnology has enabled the modifications of the agricultural materials in a precise way, thereby improving the productivity, yield and specific desirable characteristics. Specifically the field of recombinant DNA technology has resulted in the production of so called Genetically Modified Organism’s (GMO’s) into the food market. GMO’s are the organisms (Plants, animals, microorganisms etc ) in which genetic material (DNA) has been changed in way that does not occur by mating or by natural process. Genes changes continuously by natural mutation and recombination enabling man to select and breed crops having most desirable traits such as yield or flavor. Genetic modification (GM) is a recent development which allows the specific genes to be identified, isolated, copied and inserted into other plants with a high level of specificity (Shirai, 1998). Cross–breeding of plant takes a several years to acquire a desired traits but the recombinant DNA (rDNA) technique is expected to bring about great progress in the improvement of the breeding technology and the development of new plant varieties showing high quality and high yield, such as those with excellent pest and disease resistance, those with environment stress tolerance and so forth. ( Hoban, 1999). GENETICALLY MODIFIED ORGANISMS The concept of a GMO generally refers to an organism whether a plant, an animal or a micro- organisms (bacterium, fungus, yeast etc.) that has been produced using the modern biotechnology, including recombinant technology. An organism produced from genetic engineering techniques allow the transfer of functional genes to its progeny. Living modified organisms (LMOs) and transgenic organisms are other terms often used in place of GMO’s (Tozzini; 2000) A US definition of GMO”Genetically modified organisms” refers to plants and animals containing genes transferred from other species to produce certain characteristics, such as resistance to certain pests and herbicides.

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Page 1: GENETICALLY MODIFIED ORGANISMS AND CHALLENGES …home.eng.iastate.edu/~tge/ce421-521/Bishnu Karki.pdf · GENETICALLY MODIFIED ORGANISMS AND CHALLENGES ... GM crops offer distinctive

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GENETICALLY MODIFIED ORGANISMS AND CHALLENGES

Bishnu Karki

ABSTRACT Genetically modified organisms have been developed by application of advanced techniques of genetic engineering. GM crops offer distinctive advantages like insects, weed, disease and drought resistance, better nutritional value and higher yield. However in a considerable part of the world, non governmental organizations and/or the general public are hesitating or opposing the cultivation and application of GM crops. There are several environmental and public issues concerning the GMO’s.Overall, genetic engineering of the organisms, plants and animals is accepted conditionally; the gene inserted and its products should be carefully assessed both for human and environmental safety before release into the nature and to the public market. In many countries in the world, especially, those is the European Union, GM food is still considered as undesirable. Mandatory labeling is required when more than 1% of any ingredient of food which originates from the GMO. Thus, there are several research are on progress for development of the valid GMO detection method. KEY WORDS Genetically modified organism, Environmental risks assessment, herbicide resistance, Biosafety Regulations. INTRODUCTION The rapid development in biotechnology has enabled the modifications of the agricultural materials in a precise way, thereby improving the productivity, yield and specific desirable characteristics. Specifically the field of recombinant DNA technology has resulted in the production of so called Genetically Modified Organism’s (GMO’s) into the food market. GMO’s are the organisms (Plants, animals, microorganisms etc ) in which genetic material (DNA) has been changed in way that does not occur by mating or by natural process. Genes changes continuously by natural mutation and recombination enabling man to select and breed crops having most desirable traits such as yield or flavor. Genetic modification (GM) is a recent development which allows the specific genes to be identified, isolated, copied and inserted into other plants with a high level of specificity (Shirai, 1998). Cross–breeding of plant takes a several years to acquire a desired traits but the recombinant DNA (rDNA) technique is expected to bring about great progress in the improvement of the breeding technology and the development of new plant varieties showing high quality and high yield, such as those with excellent pest and disease resistance, those with environment stress tolerance and so forth. ( Hoban, 1999). GENETICALLY MODIFIED ORGANISMS The concept of a GMO generally refers to an organism whether a plant, an animal or a micro- organisms (bacterium, fungus, yeast etc.) that has been produced using the modern biotechnology, including recombinant technology. An organism produced from genetic engineering techniques allow the transfer of functional genes to its progeny. Living modified organisms (LMOs) and transgenic organisms are other terms often used in place of GMO’s (Tozzini; 2000) A US definition of GMO”Genetically modified organisms” refers to plants and animals containing genes transferred from other species to produce certain characteristics, such as resistance to certain pests and herbicides.

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A GMO is defined in council directive 2001/18/EEC as an organism in which the genetic material has been altered in a way that doesn’t occur naturally by mating and/or natural recombination. In recent years, cultivation and/or commercialization of several GMOs has been approved worldwide in different countries, and the tendency to increase the cultivated area as well as well the number of modified traits is becoming evident (James, 2001). However, the norms that regulate the use and exploitation of GMOs differ from one country to another, and they are probably influenced by consumer perception (Kleter et al., 2001). In 2004, the global area of biotech crops continued to grow for ninth consecutive year at a sustained double digit growth rate of 20%, compared with 15% in 2003. The estimated global area of approved biotech crops for 2004 was 81.0 million hectares up from 67.7 million hectares in 2003. (James, 2004). The current trends in the development of the GMOs are towards the crop improvement mainly focused on the development of herbicide-tolerant crops and on pest and disease resistant crops. Transnational corporations such as Monsanto Dupont, Novartis, etc. which are the main proponents of biotechnology, view transgenic crops as a way to reduce the dependence on input such as pesticides and fertilizers (Altieri,1998). Crops Available That Have Been Genetically Modified

Corn Soyabean Cotton Papaya Cotton Canola Cauliflower

Tomato Potato Cabbage Alfa-alfa Sugarcane Rice Peppers

Tobacco Diagrammatic Representation Of Genetic Engineering In Plant.

Electroporate T-DNA vector into Agrobacterium and select for tetr

Expose wounded plant cells to transformed agro strain

Induce plant regeneration and select for Kanr cell growth

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Can We Differentiate Between GM And Non- GM Crops? GM crops which are considered threatening by some people, are crops in which scientist inserted desirable genes by DNA technology. The inserted genes can be from other plants or other organisms. Non-GM crops are all plants in the world that have not been developed by DNA technology. These includes crops in which their DNA has been modified by crossing and/or mutation that resulted from radiation, somaclonal variation or chemicals. The science of genetics and the discipline of plant breeding have emerged only in the past 200 years, but plants have been selected and bred from prehistoric times (Murray 1993; Bulfield 2000; Polkinghorne 2000). What are the differences between the GMO and Non-GMO’s ? Usually there is no obvious morphological differences between GM and Non-GM unless the products are exposed to certain conditions that can show phenotypic differences between GM and Non-GM.(Snow and Palma 1997). In the case of herbicide resistant crops, for examples, the herbicide resistant crops will grow normally after herbicide spraying. In contrast, non herbicide resistant crops may show signs of growth retardation. The crossing behavior of GM crops and Non- GM crops does not have to be different (Institute of food Technologists 2000). For example, maize does not cross with crops such as rice or soybean, whether or not it has been genetically modified. GM crops would be able to cross- pollinate with Non-GM crops of the same species. A logic exception is male sterile GM crops that do not produce fertile microspores. It can not fertilize its own or any other macrospores of related crops. ADVANTAGES OF GMO’S Recombinant DNA technology is the most promising, precise and advanced strategy available today for sustainable global food production by reducing the crop losses and increasing the yield. The world population is increasing in the geometric progression and the World Health Organization estimates that the global population will be doubled by 2050 to more than 9 billion people. Hence, food production must also increase. The economic benefits from transgenic crops are large. Some of benefits of transgenic plants are given below Herbicide Tolerance The major or targeted crops can be made herbicide resistant. The herbicide tolerance, (mainly to glyphosate and glufosinate ammonium) introduced in Soya, oil seed rape (canola), cotton, maize and sugar beet, which allows the application of broad spectrum herbicides to the standing crops, so killing all the weeds without causing the crop damage and leading the higher yield, improved quality and lowering the input such as labor and the fuel .The strategy applied to achieve this goal is (1) increasing the level of the target protein for the herbicide by over expression (2) decreasing the sensitivity of target protein by introducing a gene coding for that protein resistant to the herbicide either naturally (or microbial source) or through specific protein engineering (3) inducing a gene encoding for an enzyme metabolizing and thus detoxifying the herbicide (Engel et al., 1995). Herbicides such as glyphosate (Roundup) and glufosinate (Basta) are broad spectrum. Glycophosate normally inhibits an enzyme (enolpyruvyl shikimate phosphate synthase, EPSPS) of essential aromatic amino acid synthesis. However resistance can be obtained through transformation with a glycophosate insensitive ESPS from Salmonella bacteria and resistance to glufosinate is derived by transformation with an enzyme that inactivates it (phosphinothricin acetyl transferase, PAT) (Skerrit, 2000). The so called “Roundup ready” soya that is genetically modified to protect against herbicides like Roundup was studied in this thesis studied. Insect Resistance There is always a high risk of plant and plant products to be lost at the various stage of development due to insects. The increase use of insecticides by the farmers all over the world may result in the environment pollution. Insects destruction and repulsion are thus the target for

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the modifications of the plants for higher productivity and are an important in field and horticultural crops as well as in plantation trees. The insects resistance transgenic crops involve modifications in the gene for the toxic proteins known as Cry 1 Ac and Cry 2 Aa from the soil bacterium Bacillus thuringiensis (Bt) (Skerrit, 2000). The insecticidal properties are due to the biosynthesis of the different toxic crystal proteins. These pro toxins are proteolytically cleaved in the midgut of the insects, binds to a specific membrane receptor and finally lead to the death of insects. For example, transformation of peas with the kidney bean amylase inhibitor gene to develop a source of resistance to pea weevils and use of cowpea gene in strawberries to confer weevils resistance (Engels et. al., 1995). Disease Resistance Most of the time, the viral and fungal attack to a crop lead to almost 100% of crop loss. Genetic modification of the plant has successfully developed plants with resistance to virus. By means of the recombinant DNA technology it has been possible to express the viral coat proteins in plants thus protecting them against the viral disease based on the first demonstration that the expression of the coat protein gene of tobacco mosaic virus in tobacco conferred resistance to infection by the virus. The creation of the viral resistant plants were based on introducing genes encoding viral coat proteins, viral replicases, viral movement proteins and defective interfering RNAs and DNAs that would confer pathogens derived resistance (Herbers K., 1999). For example, potato has been made resistant to the potato leaf roll virus (PLRV), white clover resistance to alfalfa mosaic virus. Higher Yield Of Products One of the biggest advantage of the genetic modification is that it has potential to produce the plants and animals that gives the higher yield. The possibility of the genetic modification is varied. It ranges from quality of food to changes produced by the plants animals etc. For example, GM somatotropin is a genetically engineered pharmaceutical that increases the cows milk production. The sheep have been modified in such a way that they produce a human protein. The GM insulin is the human protein produced by the microorganisms (Skirritt,2000). Improvement Of Desirable Character Genetic engineering has given a longer and better shelf lifes to the many of the food products with the enhanced taste and color along with easy handling of these food materials. The first-quality enhanced product in the market were the tomatoes containing (Flavr savr) a lower level of the product of the polygalactouronase gene. The lower activity of this enzyme means that the long pectin chains in the cell walls of the fruits are cleaved more slowly and the ripe fruit doesn’t soften quickly, thus extending its shelf life. GM orchid flowers are the examples which are genetically modified to give the colors which are not available naturally. Enhanced level of amylolytic enzymes for degrading starch for barley brewing and increased levels of glutenin flour proteins to alter dough properties in wheat are the properties that can be altered in processing the cereals (Skerritt, 2000). Nutritional And Pharmaceuticals Genetic engineering can be used to modify existing food to give them new characteristics. The enhancement of the lysine content in maize and enhanced vitamin A content in canola and rice are the present example of the nutritional enhancement. For example the use of gene that increases the amount of Vitamin A in rice. Golden rice is the genetically modified rice species that provides higher levels of vitamin A and iron. The enzyme involved in the fructan synthesis, the sucrose fructosyltransferase (isolated from Jerusalem artichoke) was introduced into sugarbeet. The transgenic sugar beet showed a dramatic change in the nature of

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accumulated sugar, 90% of the sucrose is being converted into fructan. Introduction of a highly expressed chalcone isomease led to a 70- fold increase of the amount of quercetin glucoside, which is a strong antioxidant in tomato. Producing fructan a soluble fiber increasing level of flavonoids, an antioxidant in tomato or increasing level of essential amino acids in the potato are clear examples of plant genetic modifications with possible positive effects on human nutrition (Sevenier et al., 2002). Edible vaccines for viral and diarrhoeal diseases using proteins expressed in transgenic plants is an application of potentially huge significance for developing countries. The vaccines protein is expressed in the edible parts of the fruits, vegetables, grain plant and has several potential advantages. Multiple vaccines could be produced in one plant (e.g. to all hepatitis strains) (Skerritt, 2000, Backgrounder, 2000). PERCIEVED PROBLEMS WITH GMO

The GMO or the living organisms (LMO’s) has been the topics of the debate upon their conjectural risk and biological hazard. Potential Environmental Risks Agricultural GMO poses a range of potential environmental risk. These different types of the potential environmental risks are given below. Gene Flow The first potential environmental risk is gene flow, where transgene could transfer from a GMO to wild relative and/or bacteria in soil or human guts. Bacteria and fungi are capable of capturing and using genetic material from their surroundings (for example, from decaying plant matter or micro-organisms). GM material, plants and decaying material, could possibly transfer their genes to other organisms such as bacteria.The effect of the absorbed gene in these other species is unknown The crops like sugar beet, carrot, ryegrass and white clover all have a “ high probability “ of gene flow, as wild relatives are effectively the same species as the crop. There is minimal probability of gene flow for potato, maize and tomato as they have no compatible wild relatives (Young et al.,1999). Emergence Of New Forms Of Resistance And Secondary Pest And Weed Problems Resistance had already emerged on a very large scale in modern agriculture even before the emergence of GMO’s(Georghiou 1986). There are now 500 species of insect, mite or tick resistant to one or more compounds together with more than 400 herbicide resistant weed biotype and 150 resistant fungi and bacteria( Vorley, 1998, Heap, 2000 ). Evolution of resistance can occur in the context of (1) GM crops expressing an insecticidal product eg Bt maize leading to the insect resistance or (2) GM crops leading to overuse of herbicides, leading to weed resistance. These are the risks which should be taken into account and safety measures implement. Recombination Of Virus And Bacteria To Produce New Pathogens. The third risk relates to the potential for viruses or bacteria to incorporate transgenes into their genomes, leading to the expression of novel and possibly undesirable traits. In theory, viral gene could affect human too, by surviving passage through the human gut and entering gut bacteria and human body cells. Once inside the cells, DNA could insert itself into the genome to change the basic structure and functions. This could lead to the emergence of the new diseases. Chicken flu and other such disease are examples of such problems which have potential of passing from animal to humans

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Potential Risk To Human Health As transgene results the manufacture of new products in crops, usually proteins, a risk to human arises if these products provoke an additional allergenic or immune response. Conventional Non-GM food already contains a large number of toxic and potentially toxic products and thus by transferring the genetic information, genetic engineering can destabilize the way DNA replicates, transcribes and recombines. The potential implications of genetic manipulation and human health are given in table 1. Table 1 Implication of genetic manipulation and human health (Akhter, 2001)

• Inserted gene may have adverse effects • May code for proteins that are toxic for human health • May produce an allergenic reaction • May cause activation of previously silent gene • May be transfer to the other organisms • Consumption of GMO may alter balance of existing microorganism in the gut

PUBLIC ACCEPTANCE DEBATE In public debate GMOs are often referred to as being unnatural or a violation of nature. Some people have serious moral concerns about departures from what is natural. Others are concerned about potential risk to environment arising from the combination of hereditary material moving across natural boundaries and the limits of the scientific foresight of long term consequences. Substantial equivalence has been introduced to assess novel foods, including GM foods, by means of comparison with traditional food. Besides a number of the objections concerning its scientific validity for risk assessment, the main difficulty with SE is that it implies that food can be qualified on a purely substantial basis. The notion of equivalence can provide a reference scale in which to examine the various legitimate factors involved: substance (SE), quality (Qualitative equivalence: QE) and ethics (Ethical equivalence:EE).QE requires that new qualitative methods of evaluation that are not based on the reductive principles are developed. EE can provide a basis for the development of an Ethical assurance as a counterpart of quality assurance in the food sector (Pouteau, 2002). On the whole a reliable approach based on scientific facts without any bias world help to overcome the problems associated with GM and make available the big advantage it holds. MONITORING AND LABELING OF GMO The use of the biotechnological processes, particularly genetic modification, is extremely important in devising new ways to increase food production, improve nutrient content and provide better processing or storage characteristics. It follows that when new foods or food components are developed using biotechnology, there are both national legal requirements and consumer expectations for effective systems and procedures to assess the safety of the food or food component for consumption. The advantages and potential risks arising from the application of genetic engineering in the production of foods and feeds have been the subjects of many controversial discussion (Robinson, 2001). Public skepticism has resulted in the implementation of regulatory frameworks that requires the monitoring and labeling of genetically modified organisms (GMOs). GMO labeling allows consumers to choose products according to their ethical, religious, cultural and dietary preferences. Many consumers, citing religious and ethical convictions, prefer not to use the products created by transferring genetic material across species boundaries (Akhter,2001) . Community legislation on genetically modified organisms concerning their authorization has been place since the early 1990’s and throughout the decade this regulatory framework has been further extended and refined. The main legislation that authorizes the experimental release and placing on the market of GMOs in the community is currently directive 90/220/EEC ( Frewer et al., 2004)

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European parliament and the council of the European Union (EU) have demanded the so called “Novel Foods Regulation” (EC/258/97) (Regulation (EC) No 258/97), which provides the legal basis for labeling of the foods and food ingredients containing or consisting of GMO. Because the Roundup-Ready soyabean and the Bt-176 maize were put on the market before regulation EC/258/97 came into force, labeling of products derived from these GMOs is demanded by the separate council regulation 1139/98 (Regulation (EC) No 1139/98). According to this regulation, mandatory labeling is triggered by the detection of recombinant DNA or protein expressed due to the genetic engineering. As a result the proteins and DNA have become the major targets for the detection strategies. The labeling provisions have been further specified by extending them to foods and food ingredients containing additives and flavorings derived from GMO (Regulation (EC) 50/20000 and by introducing a de minimis threshold (Regulation (EC) 49/2000). In April 2001, The European union council adopted directive 2001/18/EC, which tightened the rules on the deliberate release of GMOs. The adventitious contamination of the foods with DNA or protein resulting from genetic modification cannot be excluded. Therefore, labeling is not required if appropriate steps to avoid such contaminations have been taken and if material derived form GMO is present in the food in proportion no higher than 1% related to specific food ingredients. In consequence appropriate techniques for the quantitation of GMO in raw and processed foods had to be developed ( Engel et. al.,2003). Different countries have their own threshold level which varies from 1% to 5%. In European Union 1139/98 requires labeling of foods containing GM ingredients, especially soya and maize. 1% de minimis labeling thresholds from adventitious contamination is specified in the 49/2000. So the European Union requires the mandatory food labeling of the GM foods and has adopted a 1% threshold for affirmative GMO labeling. If any ingredients in a finished products has GMO content above 1%, the products must state clearly. The purpose of the 1% threshold is to ensure that food ingredients obtained from the Non-GM source do not need to be labeled if they contain low levels of the GM materials, as a results of accidental cross- contamination. Threshold level set by the different countries is given in table 2.

Table 2: Threshold limit for the labeling ( Popping, 2001) Labeling regulation on GMO derived food. Country/territory/Union GMO threshold limit Switzerland 1% Norway 2% European Union 1% Korea 3% Japan 5% Saudi Arabia 2% Thailand 5%

Global Status Of Commercialized Transgenic Crops /2004– Statistical View The International Service for the Acquisition of Agri-Biotech Application (ISAAA) is the international network of centers in the Kenya, the phillippines and the United states whose mission is to help alleviate hunger and poverty by sharing crop biotechnology applications. In 2004, the global area of GM crops continued to grow for the ninth consecutive year according to the report released in January by the ISAAA.GM crops planted in 2004, increased by the 20% reaching 81 million hectares globally, an increase of 13.3 million hectares since 2003. This increase represents a 47-fold increase in hectares since the introduction of the commercialization of GM crops in 1996. Table 2.3 Global status of the commercialized GM. Source.

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Global area of GM crops 1996 1997 1998 1999 2000 2001 2002 2003 2004 Million hectares 1.7 11.0 27.8 39.9 44.2 52.6 57.8 67.7 81

Source: ISAAA (2004),Ithaca, NY During the nine-year period 1996 to 2004, herbicide tolerance has consistently been the dominant trait followed by insect resistance. The herbicide tolerant trait in soybean, maize canola and cotton occupied 72% or 58.6 million hectares of the global total of 81 million hectares. The most dominate GM crops globally, herbicide tolerant soybeans, continued to increase in 2004, occupying 48.4 million hectares or 60% of the global total GM crops area and was grown in nine countries. The second most dominate crop Bt maize, occupied 11.2 million hectares equivalent to 14% of global GM crop total and was also grown in nine countries. The third grown in eight countries and over 4.5 million hectares or 6% of the global GM crop total area was Bt cotton.

Fig. 2.Trends in global agricultural growth using genetically modified crops.(James, 2004).

Global area of GM crops in 2004 by crop Soyabean Maize Cotton Canola

Million hectares 86 19.3 32 23 Percentage (%) 56% 14% 28% 19%

Global area of GM Crops by country

Million hectares

GM Crops Global Total (%)

USA 47.6 Canola, Cotton, Maize, Soybean 59

Argentina 16.2 Cotton, Maize, Soybean 20 Canada 5.4 Canola, Maize, Soybean 6 Brazil 5.0 Soybean 6 China 3.7 Cotton 5 Paraguay 1.2 Soybean 2 India 0.5 Cotton 1 South Africa 0.5 million Cotton, Maize, Soybean 1

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GMOs In Bioremediation Bioremediation is the acceleration of natural biodegradation rate through the modification of environmental conditions ( Margesin and Schinner, 1999). Several persistent organic pollutants (POPs) are major subject of concern because of their toxicity to both the animals and wildlifes. Bioremediation is cost effective method and achieve complete degradation of organic pollutants without collateral destruction of the site material or its indigenous flora and fauna thus this is the best method as compare to the physicochemical remediation (Timmis and Pieper, 1999). These are the major micropollutants. Removal of these pollutants from the wastewater and water is not easy task because these compounds are present in very small amount (nanograms). But they are highly toxic even in small amount to humans and animals. So scientists are looking for the best method to remove these pollutants. Use of microorganism for bioremediation is the best option but biodegradation of POPs by naturally occurring microorganisms takes place at very slow rate specially when multiple biodegradation traits are required. So scientist have choosen GMOs as the best alternatives for the enhanced bioremediation strategies (Ang, et al.,2005).Several insecticides like polycyclic aromatic hydrocarbons (PAHs), Polychlorinated biphenyls (PCBs), organophosphates (OP) and pesticides like Atrazine has been widely used in the field since 1950’s. These recalcitrance compound are frequently detected in the surface and ground water samples, posing a direct risk too humans via potable water consumption. There are some microorganisms and microbial enzymes which are able to degrade POPs like Pseudomonas sp and the bacterial phosphotriesterase enzymes. Biomolecular engineering can be successfully used to improve the capabilities of the enzymes or microorganisms in bioremediation systems (Ang et al.,2005). Biomolecular engineering involves on altering enzymes that can perform a reaction similar to the desired one thus it might be difficult to apply biomolecular engineering to the bioremediation of novel pollutants, which are not known to be biodegradable. And several questions are still unanswered like GMO released into the environment might have decrease level of fitness and may not survive due to the extra energy demands imposed by presence of foreign genetic material in the cell. However there are many constraints related with the release of GMOs in environment, with the recent advances in biomolecualr engineering, the prospects of short-circuiting the process of natural evolution to degrade environmental xenobiotic pollutants has been created. This has opened exciting new vistas for enhancing bioremediation in coming years. CONCLUSIONS: With the development of the biotechnology, more and more genetically modified organisms are introduced in the commercial market. Since the beginging of the GMO production it has been facing many challenges like environmental issues. Several studies have been conducted to assess the environmental effect of the GMO and its future scenario. Reports on the ecological impacts of the cultivation of certain non-transgenic crop plants with novel or improved traits as analogy models to transgenic plants showed that the effects of agricultural practice can be at least equally important as the effect of gene transfer and invasiveness, although the latter currently play a major role in risk assessment of the transgenic crops (Gaugitsch, 2002). Essentially the molecular or cell biology of an organism is being altered by means not possible under natural conditions or processes. Some techniques used to alter molecular structure include, but are not limited to, cell fusion, gene deletion, gene doubling, the introduction of a foreign gene, and changing a genes position within the DNA. This gene manipulation creates what is called genetically modified organisms, or GMOs. In my opinion, we cant say good or bad without any scientific evidences. And its being an new area of biotechnology its in the challenging stage of development and will take some more time to give us the solid results. Atleast we can hope for the best of human beings.

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REFERENCES: 1. Akhter, J. (2001). Genetically Modified foods: Health and Safety Issues. Annuals of

Saudi Medicine, 21 , 161.

2. Altrieri, M. A. (1998). The Environmental Risks Of Transgenic Crops: An Agroecolo gical Assessment. Agbiotech News and Information, 10, 405.

3. Ang, E-L., Zhao, H., Obbard, J-P (2005). Recent advances in the bioremediation of ersistent organic pollutants via biomolecular engineering. Enzyme and Micorbial Technology, 37, 487.

4 Commission Regulation (EC) No 50/2000 of 10 January 2000 on the labeling of food stuffs and food ingredients containing additives and flavorings that have been genetically modified or have been produced from genetically modified organisms. Official journal of European communities – L 006, 0015. 5 Directive 2001/18/EC of European parliament and of the council of 12 March 2001 on

the deliberate release into the environment of genetically modified organisms and repealing Council Directive 90/220/EEC – Commission Declaration. Official Journal of European Communities L 106, 0001.

6 Engel, K.H., Schauzu, M., Klein, G. and Somoyogyi, A. (1995). Regulatory Oversight

and Safety Assessment of Genetically Modified Foods in the European Union.In: Genetically Modified Foods, Safety Aspects. Engel, K.H., Takeoka G.R. Eds. American Chemical Society, Washington DC.

7. Engel, K.H., Moreano, F., (2003). Methods to Detect the Application of

Genetic Engineering in Composed and Processed Foods, PP 225-223. In:Genetically Engineered Food, Method and Detection. Knut J. Heller; ed. Wiley- VCH Verlag GmbH and Co. KGaA, Weinheim, Germany. 8 Frewer, L., Lassen, J., Kettlitz, B., Scholderer, J., Beekman, V. and Berdal, K.G.(2004).Societal Aspects of Genetically Modified Foods. Food and Chemical Toxicology, 42, 1181. 9 Hoban, T.J., (1999). Consumer acceptance of Biotechnology in the united states and Japan. Food Tech. 53, 50. 10 James, C., (2000b). Global Status of Commercialized Transgenic Crops.” ISAAA Briefs No.21: Preview.ISAAA: Ithaca.

NY.http://www.isaaa.org/publications/briefs_21.htm.

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