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Magazine 杂志:Biotechnology

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2017年01月01日

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Biotechnology

Nowadays in the news you can read a lot about biotechnology and the controversies about it and perhaps you ask yourself what it is exactly. Well, this article is going to give you a brief history of the field of biotechnology and show you that, although the word “biotechnology” was first used in 1919, we have been using biotechnology for many thousands of years in ways that are completely uncontroversial. It will also look at the more modern developments which have started intense debate.

Beer and Cheese

When you are drinking a cold beer on a hot day, or eating a delicious cheese sandwich, you can thank biotechnology for the pleasure you are experiencing. That’s right! Beer, bread and cheese are all produced using biotechnology. Perhaps a definition will be useful to understand how. A standard definition is that biotechnology (or biotech for short) is the application of science and engineering to the direct or indirect use of living organisms. And as you know, the food and drink above are all produced by the fermentation of micro-organisms. In beer, the yeast multiplies as it eats the sugars in the mixture and turns them into alcohol and CO2. This ancient technique was first used in Egypt to make bread and wine around 4000BC!

Antibiotics

Antibiotics are used to prevent and treat diseases, especially those caused by bacteria. They are natural substances that are created by bacteria and fungi. The first antibiotic was made in China in about 500BC – to cure boils. In 1928 Alexander Fleming discovered penicillin and it was considered a medical miracle. Modern research is looking at the creation of super-antibodies which can kill bacteria and viruses inside the cells that house them.

Cleaning up

Our modern consumer society produces a lot of waste which needs to be disposed of safely and without harmful end products. Environmental biotechnology can help. Indeed, the use of bacteria to treat sewage was first practised in 1914 in Manchester, England. Vermiculture or using worms to treat waste is another environmentally-friendly practise and the end product is a natural fertiliser. Bacteria have even been developed to help with problems such as oil spills. They convert crude oil and gasoline into non-toxic substances such as carbon dioxide, water and oxygen and help create a cleaner, healthier environment.

Modern times

These examples of biotechnology are accepted by most people. However, the discovery of the DNA structure by Watson and Crick in 1953 was the beginning of the modern era of genetics and the following areas of biotech are very controversial. Read on…

GM food

The genetic modification of plants and crops has been in practice for many years. This involves changing the genetic code of these plants so that they are more resistant to bad conditions like drought, floods and frost. Supporters of GM food say that it can offer the consumer better quality, safety and taste and for over a decade Americans have been eating GM food. However, things are very different in Europe where genetically modified food is very strictly regulated and regarded with deep suspicion by the public. GM food has even been called “Frankenfood” in the press, a term inspired by the novel Frankenstein by Mary Shelley. There is a great cultural divide between America and Europe over whether such food is safe to eat and will not harm the environment and the discussion is still in progress.

Cloning and stem cell research

1997 saw the birth of Dolly the sheep, the first animal cloned from an adult cell. This was a remarkable achievement which created world-wide debate on the ethical issues surrounding cloning. International organisations such as the European parliament, UNESCO and WHO all declared that human cloning is both morally and legally wrong. However, we need to make a distinction between reproductive cloning and therapeutic cloning. Nowadays the idea of reproductive cloning – creating a copy of another person - is no longer interesting for researchers. Instead therapeutic cloning is creating excitement in the biotech world. Key to this technique are stem cells, which are master cells that have the potential to become any other kind of cell in the body e.g. nerve cells, blood, heart muscle or even brain cells. Stem cells themselves have generated a lot of controversy as it was believed that only human embryos could provide them. However, it now appears that adult stem cells offer the same possibility. This would mean that a patient who suffered a heart attack could provide doctors with his adult stem cells which could then be implanted back into his heart and used to create heart muscle, replacing the muscle that was damaged. As the genetic code is identical, there would be no problem of the body rejecting the implant as, unfortunately, happens with organ transplants. In the future, biotechnologists hope that stem cells could be used to grow entire organs. In this way biotechnology offers the hope of revolutionising medical treatment.

In this brief overview of the history of biotechnology we have jumped from making bread to making human organs - an enormous leap- and it is clear that these modern practices raise many controversial issues. However, despite the debate, we can imagine that as biotechnology has been around for many years, it will still be around for some time to come - but who knows where it will take us?

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