Tuesday 21 August 2012

Genetic modification, the good the bad and the Ugly

Genetic engineering, also called genetic modification, is the direct manipulation of an organism's genome using modern DNA technology. It involves the introduction of foreign DNA or synthetic genes into the organism of interest. The introduction of new DNA does not require the use of classical genetic methods, however traditional breeding methods are typically used for the propagation of recombinant organisms. An organism that is generated through the introduction of recombinant DNA is considered to be a genetically modified organism.

The first organisms genetically engineered were bacteria in 1973 and then mice in 1974. Insulin-producing bacteria were commercialized in 1982 and genetically modified food has been sold since 1994. The most common form of genetic engineering involves the insertion of new genetic material at an unspecified location in the host genome. This is accomplished by isolating and copying the genetic material of interest using molecular cloning methods to generate a DNA sequence containing the required genetic elements for expression, and then inserting this construct into the host organism.

Other forms of genetic engineering include gene targeting and knocking out specific genes via engineered nucleases such as zinc finger nucleases or engineered homing endonucleases. Genetic engineering techniques have been applied in numerous fields including research, biotechnology, and medicine. Medicines such as insulin and human growth hormone are now produced in bacteria, experimental mice such as the oncomouse and the knockout mouse are being used for research purposes and insect resistant and/or herbicide tolerant crops have been commercialized. Genetically engineered plants and animals capable of producing biotechnology drugs more cheaply than current methods (called pharming) are also being developed, and in 2009 the United States FDA approved the sale of the pharmaceutical protein antithrombin produced in the milk of genetically engineered goats.

 A humble soil bacterium called Ralstonia eutropha has a natural tendency, whenever it is stressed, to stop growing and put all its energy into making complex carbon compounds. Now scientists at MIT have taught this microbe a new trick: They’ve tinkered with its genes to persuade it to make fuel — specifically, a kind of alcohol called isobutanol that can be directly substituted for, or blended with, gasoline.

By knocking out a few genes, inserting a gene from another organism and tinkering with the expression of other genes, Brigham and his colleagues were able to redirect the microbe to make fuel instead of plastic.
While the team is focusing on getting the microbe to use CO2 as a carbon source, with slightly different modifications the same microbe could also potentially turn almost any source of carbon, including agricultural waste or municipal waste, into useful fuel.
In the laboratory, the microbes have been using fructose, a sugar, as their carbon source. At this point, the MIT team — which includes chemistry graduate student Jingnan Lu, biology postdoc Claudia Gai, and is led by Anthony Sinskey, professor of biology — have demonstrated success in modifying the microbe’s genes so that it converts carbon into isobutanol in an ongoing process.

Unlike some bioengineered systems in which microbes produce a desired chemical within their bodies but have to be destroyed to retrieve the product, R. eutropha naturally expels the isobutanol into the surrounding fluid, where it can be continuously filtered out without stopping the production process
the researchers are focused on optimizing the system to increase the rate of production and designing bioreactors to scale the process up to industrial levels. This approach has several potential advantages over the production of ethanol from corn. Bacterial systems are scalable, in theory allowing production of large amounts of biofuel in a factory-like environment. This system in particular has the potential to derive carbon from waste products or carbon dioxide, and thus is not competing with the food supply.

Though genetically modifying  microbes for fuel production may seem like a step in the right direction, most people fear the previous experiments to enhance foods for protection from insects and plant weeds.
Scientists at the Department of Obstetrics and Gynaecology, at the University of Sherbrooke Hospital Centre in Quebec, took dozens of samples from women. Traces of the toxin were found 93 per cent of the pregnant mothers and in 80 per cent of the umbilical cords. The research suggested the chemicals were entering the body through eating meat, milk and eggs from farm livestock which have been fed GM corn. The findings appear to contradict the GM industry’s long-standing claim that any potentially harmful chemicals added to crops would pass safely through the body.

there are an estimated 15 million farmers involved with genetically modified agriculture,However, critics point out that this is still just 10% of the world's arable land area as defined by the UN Food and Agriculture Organization (FAO). About half of the global GM total is accounted for by the US - although overall, the developing world is adopting the technology faster than industrialized countries. If current trends continue, developing countries will be growing more than half of the global total within a few years. During 2010, Pakistan and Burma took their initial steps into the GM world by growing cotton modified to be resistant to insect pests.
American consumers learned that they might have eaten taco shells containing genetically modified maize with its own BT pesticide that had not been approved for human consumption. Apparently the GM food was sold as animal feed and for industrial use only, began to be sold as normal food to 300 brand named products through out US supermarkets. Despite FDA approving the crop for non human use, the company responsible for this GM crop did not secure the handling and mistakenly sent out as human food. The push to sell food quickly and to overlook the safety aspects as well as, seems to be the blame for this mistake.

Some scientists worry that GM foods is a biological pollution and that it is difficult to remove from the environment. There is no independent regulation to stop the GM food scandal from happening again and separation non GM foods with those that are, could be cross contaminated from the farmlands right down to the transportation of the crop. Despite cross-contamination, some companies have put a strict patent on their crop genetics and have sued some neighboring farmers for having plants with their GM crops. The whole issue of GM foods has been controversial, that companies can disregard GM food labeling and hold patents to their plants. Trace toxins are absorbed into umbilical cords of pregnant mothers and in the supermarkets in the United states it is a roll of the dice to wonder if you are eating from a genetically modified Crop. It seems that the best use of genetic modification is to utilize it for bio fuels. Its uses for industrial or animal feed has become scandalous, and the confusion of labeling or cross-contamination has given wide spread fear for mutant fallout or slow poisoning of the general public.

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