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Genetically Modified Foods. A presentation by Imaiya R, Devang A, Curan K, Bay Z, and Gurvir K. Introduction. What are they?. Genetically Modified Foods refer to crops that have been genetically altered to provide new and/or enhanced characteristics
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Genetically Modified Foods A presentation by Imaiya R, Devang A, Curan K, Bay Z, and Gurvir K
Introduction What are they? Genetically Modified Foods refer to crops that have been genetically altered to provide new and/or enhanced characteristics It is an effective, yet controversial method of agriculture
Introduction Development The concept behind GMF’s is not a new one Farmers have been using a basic method known as “mutagenesis” for years. Like breeding dogs, farmers used artificial selection to grow crops with desried qualities
This process, while correct, was uneffecient Genetic engineering techniques were introduced around 1994 to make the process quicker and more exact
The first commercially grown genetically modified food crop was a tomato; it was modified to ripen without softening Nowadays, products that are most commonly altered using genetics are: soybean, corn, and sugar canes
Chemical Aspect The major difference between organic and GMF’s are the increase in probability for the food in question to be toxic This means that GMFs’ molecular structure is greatly compromised GMF’s also tend to produce their own form of pesticide
However, the differences in molecular structure parallel the differences found through NATURAL genetic mutations (mutagenesis, etc.)
Biological Aspect The biology behind GMF’s is basically they process from which GMF’s are created. This process, which is known as genetic engineering, is where one or more gene(s) are taken out, essentially isolated from the DNA, and then inserted into the DNA if the other organism. Special enzymes, called restriction endonucleases, act as scissors to cut out a desired gene.There is a variety of the number of enzymes that cut, in different places, so the enzyme used is dependent on the sequence of the DNA strand surround a specific gene.
Advantages and Disadvantages The Controversy Much controversy exists concerning whether GM foods are viable. Such segregation is apparent by the ‘acceptance’ of segregated schools by specific countries: U.S.A: 44 Approvals of GM foods Canada: 42 Approval of GM foods UK: 19 approval of GM foods; only 5 on the market
Advantages Pest Resistance Crop losses due to insect pests can cause a huge financial loss for farmers and also cause starvation in developing countries. To combat insects, farmers have to use large quantities of pesticides which affects sales since consumers don’t want to eat foods that have been treated with pesticides. Also, excessive use of pesticides can cause run-off waste which can poison the water and cause harm to an ecosystem. But growing GM foods like B.T. corn significantly reduces the amount of pesticides needed as these crops have their own toxin which makes them less susceptible to insect pests.
These Foods are modified to become resilient to pest infestations therefore, saving money (although GM seeds are more expensive) and aiding the environment because pesticides and chemicals are therefore, unnecessary to maintain the health of crops.
Advantages Herbicide Tolerance Removing weed or killing weed is a time-consuming and an expensive process for farmers as they have to use large quantities of different herbicides (weed-killer) to destroy weed. But they have to be careful so that the herbicide does not affect their crop. Thus plants that are genetically-engineered to be resistant to powerful herbicides could help reduce the amount of herbicides needed while not harm the crop. Ex: Monsanto (chemical company – now also develops and markets GMF technology) has genetically modified soybeans to be not affected by their herbicide product ‘Roundup’.
Ex: Monsanto (chemical company – now also develops and markets GMF technology) has genetically modified soybeans to be not affected by their herbicide product ‘Roundup’. • Now farmers can use these soybeans which only require one application of weed-killer instead of multiple applications, reducing production cost and reducing run-off waste.
Advantages Disease Resistance Sometimes farmers lose their crops to many viruses, fungi and bacteria that cause plant diseases. Plant biologists are working to create genetically modified plants that are resistant to these diseases.
Advantages Climate Conditions Unexpected frost can kill seedlings which results in crop familiar. An antifreeze gene from cold water fish has been introduced into plants such as tobacco and potato to withstand the cold. Now these plants are able to survive the colder temperature that normally would kill unmodified seedlings.
As world population grows, it will become harder for farmers to find ideal soil to grow crops. So farmers need to grow crops in locations that were previously unsuited for plant cultivation. • Creating plants that can withstand long periods of drought or high salt content in soil/groundwater will help farmers to grow crops in previously unsuited places. • Foods can be genetically engineered to prosper in climate conditions that may otherwise be detrimental to the growth of the plant. • This can aid people in areas where regular crops will not prosper. = Future Increase in Population Less fertile soil
Advantages Nutrition Malnutrition is an issue in countries where people rely on one type of crop for their nutrition; crops such as rice. Rice doesn’t contain all necessary nutrients, hence causing deficiencies. Ex: blindness due to lack of vitamin A is a common problem in third world countries. So researchers at Swiss Federal Institute for Plant sciences have created genetically engineered rice that contains unusually high content of Beta-carotene (vitamin a). Genetically modified rice in Asia is extremely essential as it is part of their traditional diet.
However, anti GMF protests in Europe could mean that this nutritionally enhanced rice may not even enter the market at all. • Preservatives become unnecessary as the “shelf life” of these foods can be engineered to last longer before rotting therefore, nutrition is not deterred by preservatives • This also aids with importing and exporting food because expiry dates are less of a concern • Many individuals believe that genetically modified foods taste better hence, increase in nutrition appears not to detriment but enhance taste
Advantages Medicine Medicines and vaccines are expensive to produce and sometimes require special storage conditions which are not readily available in third world countries. Researchers are working on to engineer tomatoes and potatoes so that these crops can contain edible vaccines. These would not need special storage, and will be much easier to ship, don’t need injecting. The DNA system of some foods are modified in order to prevent the consumer from experiencing an allergic reaction therefore, permitting people to eat foods that they would otherwise be unable to consume. Ultimately, this contributes to the variety of food available to individuals of society.
Advantages Detoxification Soil and groundwater pollution is a huge issue in all parts of the world. So plants such as poplar trees have been genetically engineered to clean up heavy metal pollution from contaminated soil.
Advantages Economy Time can be saved as some foods can be genetically engineered to increase the speed of food production (in comparison to traditional methods). Rapid growth can aid poorer nations with greater populations as more supply becomes available to the overwhelming demand. Increased productivity helps the economy. Food production increased and developed countries by 70%, because of genetically modifying technology.
Disadvantages - Environmental Ultimate Effectiveness Just like how some species of mosquitoes evolved to develop resistance to now-banned pesticide DDT, many people think that insects will become resistant to B.T. or other crops that have been engineered to produce their own pesticides. The claim of ending world hunger with GM food is a false claim. World hunger is not caused by shortage of food production, but by sheer mismanagement, and lack of access to food brought about by various social, financial and political causes.
Disadvantages - Environmental Unintentional Gene Transfer Another question raised is that what if crop plats that engineered for herbicide tolerance cross breed with weeds, resulting in transfer of herbicide resistant genes from the crops into weeds. This would make ‘super weeds’ that are tolerant to herbicides as well which may ultimately, cause crop failure.
Other genes may cross over into non-engineered crops plant next to GM crops. • An ‘escape’ of genetic material into the environment can be extremely detrimental. • Some of the genetically modified foods contain vaccines, antibiotics, contraceptives etc. Therefore, ultimate result could be extremely hazardous to animal health and the environment. • This possibility is shown by defence of farmers that against the lawsuit filed by Monsanto. Monsanto has filed patent infringement lawsuits against farmers who may have harvested GM crops. Monsanto claims that farmers obtained Monsanto-licensed GM seeds and did not pay royalties to Monsanto. • But farmers claim that their unmodified crop were cross-pollinated from someone else’s GM crops from a couple of fields away. Although, more investigation is needed to solve this issue this is a good indication that more debates like this can take place in the future.
Disadvantages - Environmental Solutions Genes exchange between plants through pollen. 2 ways to make sure that untargeted crops will not receive the genes from GM plants are to engineer GM plants that are male sterile (can’t produce pollen) or to further modify the same GM crop to GM plants so that the pollen doesn’t contain the introduced gene. Another solution is to create buffer zones around a field of GM crops. Ex: Non-GM corn would be planted to surround a field of B.T. (GM) corn, and the non-gm corn would not be harvested. So pests would refuge in non-GM corn and could be allowed to destroy it so they will not develop resistance to B.T. pesticides.
Disadvantages - Environmental Invasive Species Comparison This whole concept of genetically modifying or enhancing fruits and vegetables is an example of invasive species, as it is only through genetic alterations that these foods are produced. This means that, similarly to the new introduction or foreign or invasive species, GMF`s also may have the negative affect that are brought to the environment through invasion species. These negative effects can be devastating to various communities around globe. Some of these affects include:
Alteration of the food chain in an environment • Endangerment of many plants, foods, and even animals • Species would become endangered as a result of their food becoming endangered or extinct • some reasons for endangerment is that the GMF`s may begin to compete for living necessities with other species, and in the end out-competing them, resulting in the food chain to be altered, as stated previously. • ) This is an example of predation, where the GMF’s, acting as the predator, are benefitting
Predation-predation is when one organism benefits off of another organism but the organism that is not benefiting is being harmed. When predation occurs not only will one species be affected but the balance of certain species population will begin to alter. This is because when one species begins to decline in population numbers other species, which are consuming these species, will have to compete more as a supplement. As the population of the food sources declines, the competition between the predators, higher up on the food chain, begins to intensify in an attempt to continue to survive.
This is one of the most crucial cons: predation, when the food chain is affected, everything species in that food chain is affected. This would have negative effects on: • Economy:food production decreases, and a lower population animals would result in things such as fewer quantities of meat and fur. Also if production of these things decreases, there would a decrease in the amount of exports occurring, having drastic effects on major companies and businesses. • Social:If foods are beings effected by GMF’s through predation, they start to face endangerment, meaning that the food stocks go down. People will have to either give up tradition foods as food prices will inflate, in order to keep constant the demand versus quantity of the product ratio. • Ethical:Even in our modern day and age, people still follow their ancestral customs of living. They still rely on certain foods and animals to continue their lives, an example being farmers. If there is not enough production occurring then cannot make a living, let alone the fact that food production would go down.
Disadvantages – Human Health Allergenicity Many people have developed life threatening allergies to peanuts and other foods; a possibility that introducing a new gene in a plant may create a new allergen or causing an allergic reaction in susceptible individuals. A proposal to introduce a gene from Brazil nuts into soybeans was rejected due to fear of causing unexpected allergic reactions. Extensive testing of new GMFs may be required to avoid possible harm which makes GMFs expensive to put into market.
Disadvantages – Human Health Unknown Ultimate Effects Because this branch of science is relatively new, the long-term effects of genetically modified food on animals including humans remains undetermined Individuals fear that chemical additives utilized in the process of producing genetically modified foods will be detrimental to the health of the consumer. Some individuals believe that consuming GM foods contribute to diseases that are immune to antibiotics Experts have gathered evidence which suggests that consuming these foods promotes the development of cancer cells.
Consumer is unaware of how their food is genetically modified unless they research • Ex: Modified Milk Ingredients • What about it is modified? • In some countries, some countries neglect to mention on food labels that they use genetically modified foods as ingredients. • Scientists can choose which genes to manipulate, but they don't yet know where in the DNA to precisely insert these genes and they have no way of controlling gene expression. Genes don't work in isolation, changing a few could change the whole picture, with unpredictable and different effects under different circumstances. Which One’s the Modified Milk?
Disadvantages – Interesting Views Philosophical Perspective Determining whether a product is safe is extremely subjective as an individual is hindered by their emotion and perspective so although some scientists claim for GM products to be safe, the degree of safety remains debatable. Science in unable to prove a negative such as “GM products will not cause harm” – too many factors need to be considered and inductive reasoning (which is flawed) from tests must be employed.
Disadvantages – Interesting Views Religious Perspective Religious and cultural communities fear the consequences of interfering with nature. Mixing plant genes and animal genes together is not a comfortable idea for some individuals Crosspollination between animals and plants can have potential detrimental effects on other organisms existing within an environment Ex: Flora and fauna diversity will decrease