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Retrospect

Revolution in the field

20 years ago, the first genetically modified plants appeared

Year 2003 is not yet over, but it has already been marked by the great controversy over genetically modified organisms, or transgenics. This is also the year that sees the completion of 30 years from the beginning of genetic engineering and 20 years from the first experiment with a plant using techniques of biotechnology. In 1972, American geneticists Stanley Cohen and Herbert Boyer developed the technology of recombinant DNA, a methodology for joining artificially parts of DNA (deoxyribonucleic acid) that are not found together in nature. It was this technique that made it possible to transfer genes of one species to another.

One year afterwards, researchers from the universities of California and Stanford isolated a gene of a toad of the Xenopus genus and inserted it into the DNA of the Escherichia coli bacterium. The result was what was expected: the bacterium started to produce a specific protein that existed in the toad. In 1983, there was a further significant advance for science, which was to cause a revolution in agriculture. A team from the University of Washington, in Saint Louis, United States, led by Mary-Dell Chilton, presented at a congress in Miami the results of the first successful genetic manipulation in plants. The researchers incorporated a gene from the Agrobacterium tumefaciens bacterium into a common species of tobacco (Nicotiana plumbaginifolia ) with biotechnology techniques, and left the plant resistant to the kanamycin antibiotic.

Oddly enough, another two groups presented similar works at the same conference. Jeff Schell and Marc van Montagu, from Ghent University, a Belgian institute, also worked with tobacco. Ernest Jaworski, Robert Fraley, Stephen Rogers and Robert Horsch, from the Monsanto company, from the United States, used the petunia. The techniques for manipulation and the rules on biosafety became more developed, and in 1994 the first genetically modified foodstuff, the FlavrSavr tomato, more resistant to transportation, bigger and tastier, began to be marketed in the American market.

Nowadays, there are plants that are resistant to herbicides, insecticides and insects. The estimate for 2002 was that 45% of the soybeans, 11% of the corn and 20% of the cotton produced in the world was already genetically modified, such has been the advance of biotechnology in the world in the United States alone, in 2003, 38% of the corn, 80% of the soybeans and 70% of the cotton planted in the country are transgenic.

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