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Thursday, April 7, 2011

Benefits & Risks of Genetically modified Organisms (GMOs)


Benefits & Risks of Genetically modified Organisms (GMOs)
Genetic engineering and GMOs:

Genetic engineering or genetic modification is an all-inclusive term to cover all laboratory and industrial techniques used to alter the genetic make up of an organisms by mixing the DNA of different genes and species together.

This process of recombining DNA is genetic engineering or genetic modification and the living organisms made with altered DNA are called Genetically Modified Organisms (GMOs). However, the process is not so simple as precisely cutting out one gene with the help of enzymes called restriction enzymes and putting it into another place called ligation done with with th of ligating enzymes, since genes are surrounded by other sequences in the DNA that determine whether a gene of one organism can function in another organism or not. So a careful study of the GMO is needed for us to be sure of its safety. Genetic engineering can be used for good causes and also can be misused.

Genetic Engineering has immense potential, is rapidly developing, and it can be used for beneficial purposes but there are also risks. It is also a sophisticated technology and needs developed laboratory facilities and particular environmental conditions that require investment.

Many kinds of GMOs are developed for environmental purposes and for health and medicine. Genetic engineering has been particularly successfully used and applied in food and agriculture to produce genetically modified foods.

Environmental use of GMOs

Oil spills and oil in waste discharged into the sea from refineries, factories or shipping contain poisonous compounds that are dangerous to welfare of all living beings, including plants and animals and other wildlife. Bio-remediation is a natural process occurring very slowly in which the bacteria and other micro-organisms breakdown oil into other harmless molecules. With environmental pollution on the increase, scientists are developing genetically modified bacteria that can effectively and rapidly digest oil and that are well suited to particular environmental conditions. They are also used to remove algae from ponds and lakes. They are also used for manufacture of useful chemicals such as enzymes for plants by providing renewable resources of industrial chemicals.Use of GMOs for environmental clean up has been used in various parts of the world. Not many ethical concerns have been raised against this purpose. However, what is interesting is that in general the natural genetic engineering done by gene exchange between bacteria in the soil or water makes so many different bacteria that are selected to use the toxins for their energy source, and these bacteria are better suited to local environments. So usually by adding fertilizer to a polluted area, the already existing bacteria will be able to grow well and clean up the pollution rather than adding new ones.
Dr. chakraborthy has developed superbug bacteria containing 4 groups of plasmids OCT plasmid degrading octane, hexane and decane, XYL plasmid degrading xylene and toluene, CAM plasmid degrading camphor, NAH plasmid degrading naphthalene, which can clean up oil spillage.
Deinococcus radiodurans can clean up the fraction of organic waste present at radioactive sites.
Scientists have developed Bacteria thet are engineered to degrade plastics .

Genetic engineering in Food and Agriculture

Use of genetic engineering technologies in food and agriculture to produce genetically modified (GM) food has been very controversial. Genetic engineering has been used to produce transgenic plants that carry several enhanced characteristics by inserting genes from various organisms. Genetic engineering is used in agriculture to make plants with increased yield, disease resistance, pest resistance like Bt genes to kill selectively pests that eat crops. There have also been fruits and vegetables modified for long term storage or delayed ripening that remain fresh for long time, which is useful also during transportation to the market. Over 15 countries of the world use GM crops for the general food production already.

The second wave of GM plants includes those with high nutritional content and improved food quality like golden rice, plants that can tolerate high salt levels in the land or are modified so that they can grow in harsh conditions like drought.

Some of the examples

Rapeseed - Resistance to certain pesticides and improved rapeseed cultivars to be free of erucic acid and glucosinolates
Honey - Honey can be produced from GM crops. Some Canadian honey comes from bees collecting nectar from GM canola plants. This has shut down exports of Canadian honey to Europe.
Cotton - Resistant to certain pesticides -
Rice - Genetically modified to contain high amounts of Vitamin A.
Soybean - Genetically modified to be resistant to herbicides
Sugar cane - Made resistant to certain pesticides.
Tomatoes - Made for a longer shelf life and to prevent a substance that causes tomatoes to rot and degrade. Flavrsavr
Corn - Resistant to certain pesticides.
Sweet corn - genetically modified to produces its own insecticide. .
Canola - Canola oil. May include edible oil products, fried foods, and baked products, snack foods.
Potatoes – with increased starch content
Papaya - The first virus resistant papayas were commercially grown in Hawaii in 1999. Transgenic papayas now cover about one thousand hectares, or three quarters of the total Hawaiian papaya crop. Monsanto, donated technology to Tamil Nadu Agricultural University, Coimbatore, for developing a papaya resistant to the ringspot virus in India.
Banana – High yielding varieties
Tobacco -The company Vector has a GMO tobacco being sold under the brand of Quest® cigarettes in the U.S. It is engineered to produce low or no nicotine.

Genetic engineering in health and medicine

Some GM food such as golden rice and also bananas with vaccines is being developed especially for health purposes. Golden rice has increased levels of beta carotene which is considered to be especially beneficial for people with vitamin A deficiency. Already there are successful attempts to transfer human genes that produce useful proteins into sheep and cows milk, so that they produce, for instance, the blood clotting agent factor IX to treat hemophilia or alpha-1-antitrypsin to treat cystic fibrosis and other lung conditions, also naturally occurring polyclonal antibodies for which at present there are only human donors.

Genetic engineering in medicine has been long researched for transplantation purposes, for example, to make organs or body parts like valves for the heart from pigs. There are still safety concerns about large organ transfer from other species (xenotransplants). The most controversial form of genetic engineering in medicine is the use of cloning technology to create organs for transplantation purposes so that they are immunologically compatible. There are fears that it could be misused for cloning human beings or making genetically enhanced "designer babies", so that parents can select, chose and improve the characteristics of their babies, like blue eyes, fair skin, tall, boy or girl, etc. However, the success rate of cloning is very low and its applications are still in very early stages of research.

Ethical concerns in genetic engineering

As discussed above, because genetic engineering is thought to be a new technology, some doubts, fears, concerns have been raised. One way we can consider these concerns under two kinds of ethical arguments: extrinsic ethical concerns and intrinsic ethical concerns.

a) Extrinsic concerns: These concerns are based on the doubts about the technology, its potentiality, newness and applicability to all life forms. The people in favour of technology think that genetic modification provides a great opportunity for solving hunger, food insecurity, and malnutrition in the world since it can be made for all environmental conditions and help in increasing quantity and quality of food. At the same time, there are fears raised about the safety of the food in eating and also risks to one's health since it is considered as a new technology and people fear that some genes will be transmitted to them.
Also many people think genetic engineering is unnatural and call it as Franken foods. However, it is not possible to differentiate GM food from other conventionally grown foods since both look the same, may even taste the same, unless it is mentioned on the labels of the packets. It is difficult to say whether the food is safe or unsafe given that in some parts of the world, like in the USA, people have been eating GM food for a decade but in other parts of the world, especially in Europe, many people are not willing to accept GM food because of fears of risks and other ethical concerns.
Many NGOs in the world have also raised the concern that growing genetically modified crops will be harmful for the environment and genetic modification will result in "superweeds". For example, if herbicide resistance genes from canola will flow into weedy relatives to make them resistant to herbicides. Scientific studies have not supported this fear.
Also it said that GM crops are unsafe for other organisms that feed on them, for example, some people claimed Bt toxin kills Monarch butterfly larvae. Extensive scientific studies found this was not true, however, these stories are still found on the Internet and in some NGO circles.
There is a fear that GM crops and foods will result in the loss of our biodiversity. Also, since the technology is new and needs lots of investment, it would be unfair to small farmers in poor countries. These are valid concerns and demand scientific interventions. However, the scientific studies have not been conclusive, there may be benefits in some environments and societies and not in others. There have been reports both in favour and against genetic modifications which are confusing people.

b) Intrinsic concerns: intrinsic concerns are based on how people view life, nature, religion, their personal emotions and values.  There is a feeling that mixing up genes in the organisms for our use is "Playing God" and human beings should not intervene in God's realm. Crossing natural species boundaries is creation of new life forms and inventing a new world through technology. Genetic engineering disrupts the beauty, integrity, balance of nature and might harm life. However, at the same time we can say that high tech medicines involves playing with God and agriculture was started by disrupting nature. Also hybrid plants and animals like mules are cross-species organisms and exist. In fact mules have been cloned and can reproduce in that way!
It is also argued that people eating meat harm the life of sentient beings (See the chapter on Animal Rights). Supporters of GM food consider these concerns are not valid and do not provide any solution to pragmatic issues like saving the environment and improving environmental conditions, solving hunger and malnutrition, preventing loss of biodiversity etc.
References:

Wikipedia
Internet sources