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Transgenic Technology
发布时间:2015-06-10 浏览次数:

In the past, people rarely discussed whether the food we are eating comes from transgenic technology or not. Whereas nowadays magazine articles giving researches on the advantages and disadvantages of genetically modified food bombard us from all sides. What’s more, there is a growing awareness that that kind of technology is not as good as it looks like, because there are many serious problems that conceal in it. To follow the stream, I give you detailed introduction of that technology.


What is transgenic technology?
Compared with former biological technologies, transgenic technology a mysterious method to the public. The term transgene describes a segment of DNA containing a gene sequence that has been isolated from one organism, which is inserted into a different organism. It’s rather different because it transfer some helpful genes from one creature to another with some specific biochemistry and molecular biology methods. And classified by methods, it is called artificial transgenic and natural transgenic. In terms of target objects, it can be classified into plant transgenic technology, animal transgenic technology, germs transgenic technology.

 

History
Transgenic technology has been a controversial subject since 1971 when the first genetically modified (GM) organism was developed. Concerning biosafety of genetically modified crops, field trials of GM crops should be assessed before commercialization. In the 1970 and 1980s, scientists passed this hurdle by inventing procedures for combining the DNA of two vastly different species. In 1974, Cohen has managed to move penicillin resistant gene on staphylococcus aureus plasmid into bacillus coli. The experiment that Cohen did has lifted the curtain of a new era of the transgenic technology application. China was the first country to commercialize transgenic in the early 1990s with the introduction of virus resistant tobacco. Since 1996, the GM crops commercialization has been keeping consecutively increasing. Commercial release of GM cucumber needs mandatory safety testing and regulatory assessment in avoid of hazardous effects on humans and environment in a long time.

 

Applications
Genetic transformation is an important technique for studying the molecular biology of plants, and especially can be used to understand gene function and develop genetic modified plants. On account of its particularity and splendid prospect, more and more countries are pumping more money and energy into it.  In general, this technology is often applied to medical science. For example, this technology is routinely used to introduce human disease genes or other genes into strains of laboratory mice to study the function or pathology involved with that particular gene.        The first batch of transgenic food such as tomato has been put into production since 1993. Until 2013, GM food has taken up 60% of the processed food in the US. Even in China, the GM food also has gradually invaded into the course of food processing in an anonymous way.  What’s more, gene splicing technology has been used to alter the gene products under the direction of what people want. As well, there comes many genetically engineering vaccines by using that technology.

 

Advantages
As we all know, transgenic technology has brought human numerous benefits. By the transgenic technology, scientists can modify the genetic material of the creatures to improve their properties, nutritional content and economic value in order to meet the demand of human beings. The Transgenic Technology is an efficient way to enhance resistance to rice blast fungus in rice breeding, which largely reduce the application of pesticide and chemical fertilizers. Professor Yuan Longping has said that, “People are not mice, we can’t risk so many people’s health and safety of doing experiment. The function of transgenic insect-resistant plants come from toxic protein. Though insects are dying, we truly do not know that toxic protein could do harm to our body or not. From a scientific point of view, the genetically modified is the direction of scientific development.  Now we can transfer the maize gene to rice, so that we can improve the photosynthesis of rice, this kind of transgenic technology is very good without any problems. ” The Transgenic Technology has been applied to not only agriculture but also medical treatment, such as genetically engineering vaccine. What’s more, in generally, it is beneficial to the environment.


Disadvantages
However, as the old saying goes, “Science is a double-edged sword.” The disadvantages of transgenic technology are things that we can’t ignore.  After all, the technology is still not completely mature. For example, although wheat transgenic technique has been established for many years, it still maintains a low transformation frequency. As a result, there is no transgenic wheat variety bred and released through this technique up to now. For example, in 1997, a Germany farmer started cultivating a kind of genetically modified corn. To his delight, the corn was growing very well in the early years of his usage of that corn. However, his happiness in harvest did not last too long. The disaster came to him when he fed his cows with the corn. He found that cows which had eaten the corn for a while had diarrhea and stopped producing milk. As a consequence, he has lost seventy cows in total. As for transgenic technology, people know very little about the conceivable hazard of transgenic organism because of the lack of a large amount of samples and long time for scientific research. The human race has methodically improved crop plants through selective breeding for many thousands of years, but transgenic technology allows that time-consuming process to be accelerated and exotic traits from unrelated species to be introduced. However, in some researches, G.M food is said to be likely to weaken the immunity system and cause some serious diseases.

 

Concerns
The ethical debates about the Transgenic Technology mainly involve such principles: benevolence, no harm, autonomy, justice and respect for nature. GM crops are today very rare in Europe, public opinion towards the technology remains largely negative. Some African nations also be opposed to engineered crops, even to the point of rejecting international food aid containing them. Transgenic technology has low transformation efficiency, high randomness, low repeatability and other issues. The narrow sources of target genes, owing to lacking of high-expression promoter and effective vector and other factors, limit the development application and promotion of transgenic technology. Besides, it’s more difficult for new genes to express in animals than in plants. However, on the other hand, transgenic animals can bring more economic benefits for human beings.


Actions
Despite there exists many controversies, the prospect of transgenic technology is rather promising. The first phenomenon is that cultivation if varieties have sped up. Because conditions of the science study have been satisfied gradually, gene cloning technology has enormously progressed. As a result, many new gene products are being produced. The second phenomenon is that the scale on Industrialization of transgenic technology has been expanded at a high speed. The third phenomenon is that ecological and economic effect is very remarkable. For example, it can reduce greenhouse gas emissions and it has done that. FAO (Food and Agriculture Organization) and WHO (World Health Organization) has been organizing workshops and consultations on the safety of transgenic food since 1990. At the Joint FAO/WHO Consultation in 1996, it was recommended that the safety evaluation should be based on the concept of substantial equivalence, which is a dynamic, analytical exercise in the assessment of the safety of a new food.

 

Conclusion
Up to now, there is no transgenic food safety evaluation process and no corresponding standards and regulations in most countries. Governments have to take action to administrate transgenic foods more seriously, and call for rational consumption. we should have a dispassionate look at the transgenic technology. In other words, we should treat that fairly and objectively instead of carrying too much prejudice. “The development road of new things is tortuous, but the prospects of new things are bright.” As far as I’m concerned, we should support the development of it instead of strangling it. To avoid many disadvantages coming from the technology, what we should do is to conduct the direction and the speed of the development.

 

Editor: Shi Yingfeng Source: English Net

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