GENETICALLY MODIFIED ORGANISMS (GMO)
PROBLEM BASED LEARNING (PBL2)
SHAHRUL NIDZAM BIN ROZALI M20082000098
MOHD YUZI BIN MOHD YUSOF M20082000352
NOR BAHIYAH BINTI BAKAR M20082000113
NORMALA BINTI HASHIM M20071000205
ZURAINY BINTI MD ISA M20082000356
MASTER IN EDUCATION (BIOLOGY)
GMO stands for genetically modified organism. The acronym can be applied to plants, animals or microorganisms, whereas the term genetically engineered microorganism (GEM) refers only to bacteria, fungi, yeast or other microorganisms. In both cases, however, these terms refer to a living organism that has been genetically altered using molecular genetics techniques such as gene cloning and protein engineering.
Genetically Modified Organisms (GMO) is an organism whose genetic material has been altered using genetic engineering techniques. These techniques, generally known as recombinant DNA technology, use DNA molecules from different sources, which are combined into one molecule to create a new set of genes. This DNA is then transferred into an organism, giving it modified or novel genes. Transgenic organisms, a subset of GMOs, are organisms which have inserted DNA that originated in a different species. Some GMOs contain no DNA from other species and are therefore not transgenic but cisgenic.
GMOs can be produced by gene cloning methods in which a non-native gene is introduced and expressed in a new organism. Generally the new protein has also been somewhat modified, or engineered, for proper expression in the new host. In particular, differences between microorganisms and eukaryotic cells must be overcome, such as the presence or absence of introns, occurance of DNA methylation and certain post-translational modifications to the protein itself for proper transport within or between cells. The advent of PCR and gene sequencing methods have opened up the door to all sorts of manipulative techniques for changing the structure of proteins through genetic alterations.
Genetically Modified (GM) foods are produced from genetically modified organisms (GMO) which have had their genome altered through genetic engineering techniques. The genes of plants can be modified to make them more resistant to unfavorable growing conditions and also to produce higher yields with the use of lesser fertilizers and water. Involving genetically modified organisms (GMO) which are potential environmental hazards. Examples of this GM food are; soybean, corn, canola and cotton seed oil.
The introduction of bacterial genes into cash crops, to enhance their growth, nutritional value or resistance to pests, is becoming rather commonplace in plant technology. One example that has made frequent headlines is the introduction of bacterial genes for natural pesticides into plants, in order to eliminate the need for chemical pesticide use. The drawback to this technology is public concern over the consequences of injesting these natural pesticides. Problems such as these might be alleviated by site-specific expression of the gene, or control of expression throughout the lifecycle. For example, it might cause less concern if expression of a pesticide gene in the leaves of young plants could be used to prevent foliage from being destroyed early on, without expression in the fruit later in the lifespan.
In the early 1990's, it was proposed that newly emerging genetic techniques could result in GEMs, or "superbugs", for bioremediation, that could withstand extreme conditions and rapidly break down the recalcitrant chemicals plaguing our waste sites and brownfields. Issues such as how to control the spread of these superbugs and prevent an ecological upset have hindered their development. Numerous proposals have been put forth and tested, from programmed cell death mechanisms to bioindicators to track their spread. However, the bioremediation industry today has not been able to fully take advantage of the technology available for developing microorganisms that can quickly eliminate some of our most toxic environmental contaminants.
Despite efforts to control gene expression there are many unanswered questions and issues that arise and stand in the way of full acceptance of GMOs by the public. Fear of the unknown is one cause of public reluctance to use GMOs and GEMs. However, this concern is validated whenever a specific case proves the technology has gone awry, and is widely publicized. Examples of this are products that have allegedly caused the mass destruction of non-target insect populations by genetically modified cash crops or bioethical issues surrounding questions of seed ownership once a crop has been harvested, and issues over the cost of seeds and availability to farmers.
Arguments against the use of GMOs include industrialization of agriculture, pushing out the small farmers in favor of mass production of crops and due to legalities surrounding IP and ownership of seeds. Another argument is that exports of less developed countries will suffer while over-developed states take over. An example of this is use of biotech sweeteners instead of sugarcane products from the Third World. In addition to these arguments there are countless claims of toxicity and carcinogenicity of biotech foods, which may or may not be warranted, depending on the individual products.
Those opposed to the use of GMOs are also opposed to mass production of pharmaceuticals using cloned genes in plants, or fermentation products of yeast, bacteria or fungi. The benefits, however, to using this technology, might include reduced drug costs and greater availability, assuming, of course, that the technology is properly shared and applied and used for the good of everyone.
Cloning of animals has proven to be a complicated and risky endeavor. Cloned pigs, sheep or other animals experience a long list of illnesses and complications that usually result in premature death. Strong opposition to all GMOs, however, cannot be based on these facts alone. The insertion of a single gene into a plant, for the production of a drug that will be harvested and purified, is far less risky than cloning an entire pig with a human heart in order to harvest that heart for a human transplant patient. Likewise, cloned pesticide genes in food crops might be considered more risky, as they could affect the local insect population and upset the balance of nature, or adversely affect individuals who eat that food. Advocates for mandatory labelling of foods containing, or produced using GMOs, cite risks from unknown toxins or allergens that might be introduced during production, as their reason for caution.
3.0 THE INVENTIONS
Bacteria were the first organisms to be modified in the laboratory due to their simple genetics make up. These organisms are now used for several purposes and are particularly important in producing large amounts of pure human proteins for use in medicine.
Genetically modified bacteria are used to produce the protein insulin to treat diabetes. Similar bacteria have been used to produce clotting factors to treat haemophilia and human growth hormone to treat various forms of dwarfism. These recombinant proteins are safer than the products they replaced, since the older products were purified from cadavers and could transmit diseases. Indeed the human-derived proteins caused many cases of AIDS and hepatitis C in haemophilliacs and Creutzfeldt-Jakob disease from human growth hormone
In addition to bacteria being used for producing proteins, genetivally modified viruses allow gene therapy, which is a relatively new idea in medicine. A virus reproduces by injecting its own genetic material into an existing cell. That cell then follows the instructions in this genetic material and produces more viruses. In medicine, this process is engineered to deliver a gene that could cure disease into human cells. Although gene therapy is still relatively new, it has had some successes. It has been used to treat genetic disorders such as severe combined immunodeficiency, and treatments are being developed for a range of other currently incurable diseases, such as cystic fibrosis, sickle cell anemia and muscular dystrophy.
For instance, the bacteria which cause tooth decay are called Streptococcus mutans. These bacteria consume leftover sugars in the mouth, producing lactic acid that corrodes tooth enamel and ultimately causes cavities. Scientists have recently modified Streptococcus mutans to produce no lactic acid. These transgenic bacteria, if properly colonized in a person's mouth, could reduce the formation of cavities. Transgenic microbes have also been used in recent research to kill or hinder tumors, and to fight Crohn's disease. Genetically modified bacteria are also used in some soils to facilitate crop growth, and can also produce chemicals which are toxic to crop pests.
3.2 Transgenic animal
Transgenic animals are used as experimental models to perform phenotypic tests with genes whose function is unknown. Genetic modification can also produce animals that are susceptible to certain compounds or stresses for testing in biomedical research. Other applications include the production of human hormones such as insulin.
In biological research, transgenic fruit flies (Drosophila melanogaster) are model organisms used to study the effects of genetic changes on development. Fruit flies are often preferred over other animals due to their short life cycle, low maintenance requirements, and relatively simple genome compared to many vertebrates. Transgenic mice are often used to study cellular and tissue-specific responses to disease. This is possible since mice can be created with the same mutations that occur in human genetic disorders, the production of the human disease in these mice then allows treatments to be tested.
Transgenesis in fish with promotors driving an over-production of growth hormone (GH) has resulted in dramatic growth enhancement in several species, including salmonids, carps and tilapias. These fish have been created for use in the aquaculture industry to increase meat production and, potentially, reduce fishing pressure on wild stocks. None of these GM fish have yet appeared on the market, mainly due to the concern expressed among the public of the fish's potential negative effect on the ecosystem should they escape from rearing facilities.
3.3 Transgenic plant.
Transgenic plants have been engineered to possess several desirable traits, including resistance to pests, herbicides or harsh environmental conditions, improved product shelflife, and increased nutritional value. Since the first commercial cultivation of genetically modified plants in 1996, they have been modified to be tolerant to the herbicides glufosinate and glyphosate, and to produce the Bt toxin, a potent insecticide.
The coexistence of GM plants with conventional and organic crops has raised significant concern in many European countries. Since there is separate legislation for GM crops and a high demand from consumers for the freedom of choice between GM and non-GM foods, measures are required to separate foods and feed produced from GMO plants from conventional and organic foods. European research programmes such as Co-Extra, Transcontainer and SIGMEA are investigating appropriate tools and rules. At the field level, biological containment methods include isolation distances and pollen barriers.
4.0 ADVANTAGES OF GENETICALLY MODIFIED ORGANISMS
4.1 Production edible vaccines or medicines
The approaches to produce an edible vaccines or medicines in milk, eggs or fruit in order to facilitate distribution of therapeutic or preventive molecules. Medicines or vaccines produced in milk could be manufactured and distributed cheaply and made more accessible to people around the world. Edible vaccines would help to avoid these inconveniences and dangers. There are examples of transgenic plants that have been developed to immunize against the Hepatitis B and Norwalk viruses Researchers have also produced a variety of transgenic potatoes that contain a small portion of the cholera toxin and immunize against the disease upon ingestion. In 2004, the European Union Sixth Framework Programme awarded the Pharma-Planta Programme a grant of € 12 million to genetically modify plants to grow vaccines against rabies and tuberculosis, and eventually, diabetes and HIV.
4.2 Producing functional food or nutraceuticals with added traits
Producing functional food or nutraceuticals with added traits that could make them beneficial for health or for preventing diseases, and producing food for disadvantaged consumers, affected by food allergies or intolerances as well as biofortification of the micronutrient content of food crops. An example of nutraceuticals can be tomatoes with increased lycopene (an antioxidant, which is a useful agent in the prevention and treatment of prostate cancer and heart disease) content or a soybean protein (alpha-glycinin) mutated to exhibit antihypertensive properties – the mutated protein has been purified from the soybeans and was able to lower blood pressure in hypertensive laboratory animals. Another example is a GM rice variety that supplements the vitamin A synthesis pathway. Vitamin A deficiency is a serious burden on the health of millions of children living in developing countries who cannot afford alternative sources of the vitamin, and it causes up to 500 000 cases of childhood blindness and 2–3 million deaths annually. The most famous of such crops is Golden Rice, which was developed to contain a beta-carotene supplement (a precursor to vitamin A)
4.3 Improving the qualities of certain crops and producing safer food.
It has been reported that the use of some conventional varieties of crops can have grave health consequences. For example, most varieties of Lathyrus sativus, a lentil formerly grown widely in North India and now spreading in Ethiopia, are known to cause the crippling disease of lathyrism, and traditional varieties of cassava in Nigeria also have dangerously high levels of hydrocyanic acid. Research on GM crops could create safer varieties of these and other crops that could replace harmful traditional varieties by reducing the levels of undesirable substances including mycotoxins, alkaloids, and glucosinolates
4.4 Breeding with increased yield while reducing the use of pesticides, improving plant adaptation to unfavorable environments
In order to achieve this advantage, herbicide-tolerant and pest-resistant GM varieties as well as virus- and fungus-resistant crops have been developed. GM technology has also been used to generate crops that are tailored to particular environments, e.g., drought resistant varieties or crops that are tolerant of high soil salinity. GM crops may offer solutions to very specific climatic conditions prevalent in developing countries and allow for more effective control of pests and fungal infections. For example, African climates vary so considerably that it is a real challenge to breed varieties that will grow from region to region, and the ability to design crops suited to particular regional climatic and environmental conditions could be beneficial to developing countries. Some GM improvements may offer additional benefits, for example, GM rice in China requires less pesticide spraying in addition to increasing crop yields.
4.5 Using GMOs in scientific and medical research.
It has been reported that genetically modified virus has had some success in targeting and destroying cancer cells, while leaving healthy cells undamaged. Cancer Research UK scientists have examined the effect of the genetically modified virus on pancreatic, lung, ovarian, liver, and colorectal cancers in vitro as well as in tumor bearing mice; the modified virus replicated vigorously within the cancer cells and spread through the tumor tissue, causing the cells to die. Genetically modified bacteria may also be able to serve as a barrier by secreting proteins protecting women against HIV infection. For example, a natural component of the vaginal microbial flora Lactobacillus jensenii has been genetically modified to secrete soluble CD4 (a protein that HIV specifically binds in order to gain access to cells and infect them) and has been shown to block laboratory strains of HIV from infecting human cells.
4.6 Using GMOs for bioremediation
Bioremediation is a method which used organisms to degrade waste materials into less toxic or nontoxic material in the environment. Naturally occurring organisms (e.g., bacteria, yeast, fungi) can be used as bioremeditors to clean up industrial or general waste such as sewage, pesticides, heavy metals, and nuclear waste. It has been suggested that genetic modification of such organisms can increase the effectiveness of bioremediation. Techniques of phytoremediation, the use of living plants to absorb toxic waste, also show substantial promise. For example, the yellow poplar (Liriodendron tulipifera) has been genetically modified to express bacterial mercuric reductase, which allows the poplar to grow in normally toxic levels of ionic mercury, which the modified poplar converts to the much less toxic elemental form of mercury up to 12 times faster than poplars that have not been genetically modified.
5.0 DISADVANTAGES OF GENETICALLY MODIFIED ORGANISMS
5.1 Health risks.
Potential health risks associated with the use of GMOs are the following:
5.1.1 Unexpected gene interactions
Different from the foreseen effects of the transferred gene construct (e.g. with synthesis of some toxic compounds). For example, some feeding studies have shown minor effects on the weight of animals fed on GM diets. It is likely that these unexpected results are linked to either the specific gene added to the GM crop tested or to the particular side effects of a genetic transformation event, which can potentially disturb metabolism.
5.1.2 Cancer risks
This risks which may appear because GM crops have higher pesticide residues than non-GM ones and the main ingredient of some pesticides, glyphosate, has been linked to increases in non- Hodgkin’s lymphoma. For example, in 1996, the US National Academy of Sciences concluded that allowable pesticide residues, on US foods would cause a million premature, fatal cancers in the next 75 years. Other GMO effects are illustrated by deaths and disabilities caused by food-supplement DL-tryptophan, produced by a genetically engineered bacterium.
5.1.3 Allergenic potential.
Allergenicity may be caused directly by the new proteins or by their interaction with usual proteins, producing a new allergen. Assessing the allergenic potential of novel foods presents major problems, since there are no reliable tests for predicting allergenicity. The possibility of creating new allergens has been identified as a risk that does not relate directly to the use of GM technology, but depends on the particular gene that has been added to a GM crop. Allergies develop when an individual is repeatedly exposed to a particular protein allergen.
5.2 Environmental risks.
Other controversial issue in this area relates to the potential risks posed by the technical manipulation of genetic material, since the effect of such manipulation on animal welfare is still difficult to evaluate. Toxicity of gene products may have a negative influence on feed composition, which in its turn may cause negative performance of fed animals. GMO-related environmental threats also include problems like pesticide plant-and-animal toxicity, and this use of GM crops will require the provision of special agronomic facilities that restrict the spread of seed and pollen.
5.3 Threat to biodiversity .
Convention on Biological Diversity defines biological diversity as the variability among living organisms from all sources including terrestrial, marine, and other aquatic ecosystems and the ecological complexes of which they are part, including diversity within species, between species, and of ecosystems. In the evolutionary history of species, spontaneous mutations that give rise to new allelic forms submit the organism to a period of adaptation to a new gene. The transformation of a single element reflects on the group as a whole. In the case of GMOs, where an exogenous gene has been inserted into a receptive organism, this network of genes is disturbed by the integration and expression of the exogenous gene. This disturbance modifies the orchestration of the network, resulting in the breakdown of epistatic relations, in provoking alterations in feedback mechanisms that regulate gene expression, in the occurrence of mutations by inactivating other genes, and other interactions that may turn genes in the host genome on or off.
5.4 Increase in social differences
It has been argued that genetic engineering policies are unfavorable for the developing countries for the following reasons:
5.4.1 Many innovations would remain unreachable for most of the citizens of developing countries even after the monopoly on patents have finished because of the differences in income when compared to the developed countries. Developing countries might also be reluctant to approve GM crop varieties because of fears of jeopardizing their current and future export markets, and they may also not be able to provide the necessary infrastructure to enable compliance with EU requirements for traceability and labeling.
5.4.2 Genetically engineered seeds may cause foodshortages, unemployment, resistant weeds, and extinction of native cultures in the developing countries. A founding principle of natural selection is that submitting an organism to pressure will increase its probability of evolutionary adaptation – this is how bacteria developed antibiotic resistance. For example, a wide-scale application of herbicide-resistant crops could eventually lead to the emergence of weed varieties that resist the particular herbicide, and target insects may become resistant to an insect-resistant GM crop through mutation and natural selection. It has also been argued that current global food production is sufficient to provide food for the world’s population, if only inequalities in access to food were eliminated, and GM crops are seen as a “technological fix,” proposed instead of undertaking economic, political, and social changes.
6.0 GM Food Labeling and the role of the Codex
In 1962, the Codex Alimentarius Commission (or Codex) was formed under the joint sponsorship of the World Health Organization (WHO) and the Food and Agriculture Organization (FAO). Its charge was to protect the health and safety of consumers and ensure fair practices in food trade through relevant standards (Lupien). Over its 40-year history, the Codex has fulfilled its mandate by establishing some 4,000 standards, recommendations, and guidelines for individual foods, food labels, pesticide residues, food contaminants, food additives, hygiene practices, and other issues relevant to traded foodstuffs (Lupien; Kimbrell; MacKenzie).
Codex members are governments representing their national interests. Standing and ad hoc committees and working groups, aided by consultations with experts from industry, scientific and civil society groups, advance the agenda of Codex. The work of these committees is slow and painstaking. It involves drafting and re-drafting proposals on food standards guided by the best science at hand and seeking to achieve consensus among members on the acceptability of such standards (Lupien; MacKenzie). Even non-controversial standards may take six or more years to develop and implement.
In 1993, the Codex undertook the task of developing labeling standards for genetically modified (GM) foods. After eight years of deliberations, however, consensus among members on such standards remains elusive (MacKenzie). Even basic elements of what is to be labeled and when a label may be necessary remain unresolved (Einsiedel; Stull). As of May 2001, the Codex working group had only agreed on some very basic definitions; progress on the key elements of a standard remains under active discussion.
The two options currently being considered within the Codex discussions reflect the opposing "product vs. process" philosophies of biotechnology regulation that have evolved over the past 15 years. If the product option were adopted, GM foods would require labeling when they are not substantially equivalent to their conventional counterparts in composition, nutritional value or intended use. Labeling would also be necessary when GM foods contain allergens or ingredients from certain fats not present in their conventional counterparts. At least this level of labeling is currently required in all countries with active food safety systems. If the process option were pursued, all GM foods and food ingredients would require labeling, regardless of whether they are substantially equivalent or not. This is the approach that has been adopted and implemented by the European Union (EU), Japan, Australia, New Zealand, South Korea and, seemingly, China.
Proponents of labels for product attributes argue that most science and expert consultations agree that mandatory labeling of all GM foods and ingredients is unjustified as these products have been found to be as safe as their conventional counterparts (Lupien). Proponents of mandatory labels for all GM products reason that consumer rights to make choices on the basis of precaution and other considerations beyond safety (e.g., personal values) should also be safeguarded (Hathcock; Mackenzie).
The disagreement on these two opposing options within Codex has implications that go beyond the philosophical discussion. Codex standards for GM food labels could have significant practical implications. In the first instance, any labeling regime for GM foods has immediate practical impact on trade, as it will establish standards for thresholds, testing regimens, traceability protocols, documentation, and allowable claims on the label. Once these are set, trading countries and companies will need to decide how to implement them. Secondly, Codex standards for GM food labels could decide any related trade disputes as they are acknowledged in the Sanitary and Phytosanitary (SPS) and Technical Barriers to Trade (TBT) agreements of the World Trade Organization (WTO) (Buckingham; Mansour & Bennett). Generally, national measures that conform to international standards set by Codex are exempt from change while those that deviate from the standard may be challenged and required to change.
6.0 The rights of the consumer
In this context labelling regulations for GMFP stresses out this consumer’s rights in the Regulation 1829/2003, regarding labelling of genetically modified food. In my opinion, the final scope of this text is respecting these two types of consumer rights:
6.1 The right to information: the aim is to guide consumers’ decisions on which food to consume, i.e. whether they accept or reject food containing GMO2. In fact, precontractual information is aimed at complementing the market economy from the point of view of the weaker party. In other words, its function is to moderate the interaction of supply and demand in favour of demand. This re-establishes a certain degree of equilibrium between resources and the respective powers of companies and consumers. EU As established in paragraph 99 of the white paper on food safety. Legislation has its own logic for precontractual stage regulations when one of the parties is legally defined as a consumer. This differential treatment is justified by evidence of the imbalance between the two parties, which leads to the need for specific solutions favouring the “weak” party only. The application of these consumer protection regulations breaks the main principles of traditional transactions (according to a liberalist economic doctrine); specifically the principles of equality between the two contracting parties (articles 1254 and 1256 CC in Spain) and freewill. In relation to this second principle, the liberalist doctrine of equality between the parties states that transactions should be carried out with a level of equality that does not exist today. Precontractual information has to be provided in the traditional process. EU legislation uses this process to redress the imbalance in transactions between company and consumer. In terms of food products, and GM food in particular, this process has brought about all of the labeling regulations. So, compliance with consumer information requirements by means of strict labelling regulations has always been an important EU issue, and this path has been followed in the GMFP in the Regulation 1829/2003.
6.2 The right to health and safety: food safety is the cornerstone of European food rights. It has led to GMO regulations in which the analysis of all possible risks predominate. Such regulations are regularly updated. Information is established as a premise in the consumer’s free decision about whether or not to buy GM food. In that very case, the right of health and security offers a very interesting approach as is using a traditional instrument for the economic rights protection: the previous information through labelling requirements. It goes without saying that in such a context, labelling of GM food products can be a main step towards consumer protection but, as we will show, the information right provided in the UE regulation is far from providing both a real choice of genetically modified food products among consumers because of some limits in the application of the previous information right that R 1830/2003 foresees.
Information-based principles for rethinking consumer protection policy, Gillian K Hadfield; Robert Howse; Michael J Trebilcock, Journal of Consumer Policy; Jun 1998; 21, 2; ABI/INFORM Global, p. 131
Labelling: competitiveness, consumer information and better regulation for the
EU, DG SANCO Consultative Document, February 2006
Journal of Genetically modified organisms: do the benefits outweigh the risks? Kristina Hug, Department of Medical Ethics, Lund University, Sweden. Deaprtment of Helath Management, Kaunas University of Medicine, Lithuania.