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E2_ Abi 2010_ Genetic engineering

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					E2, Abi 2010: Genetic engineering

   1. First, read the two texts about genetic engineering.
   2. In text 1, Five major advances in genetic engineering, evaluate the five listed items:
      are they ‘good’ or ‘bad’? Which is ‘more’ helpful than others, and which should not
      have been developed? Give your reasons using either an illustrative (plain
      positive/negative) or argumentative (pros and cons) structure.
   3. Then, read text 2: Applications of genetic engineering.
      Are there any differences in content to text 1?
      How serious is the use of argumentative structure here? Can it really show positive or
      negative aspects of genetic engineering?
   4. Explain the last paragraph:
      ”Genetic engineering is a valuable technology, but it is not without its faults and
      technical difficulties. There is also no such thing as absolute safety or zero risk. Every
      new technology has some risk attached to it. As long as the benefits far outweigh any
      negative effects, and that everything possible is done to ensure that those risks are
      minimal, new technologies, including genetic engineering should be pursued with
      vigour. The biggest risk may be in not pursuing them?”
      Is that an example for rationalization or a serious end to a serious article? Why has the
      auhtor probably chosen to give a question as the last sentence?
Text 1:

Genetic engineering has been making headlines since the technology first came to
the public's attention. Although the achievements haven't lived up to the hype or
expectation of some, there have still been some stunning advances. Here are five of
them.


Genetic Engineering Advantages

Genetic engineering is the ability to be able to change part of an organism's genome
to create some desired or beneficial trait. Of course humans have been doing that for
thousands of years with the selective breeding of cattle and crops, but the advantage
of genetic engineering is that we can now go directly into a genome and insert or
remove a chunk of DNA to create something beneficial.


Five Major Advances in Genetic Engineering
       Genetic engineering came of age in 1973 when Herb Boyer and Stanley Cohen created
        the world's first genetically engineered organism. They were able to cut a bacterial
        plasmid with enzymes and insert DNA into the gap that was created. The ultra-
        revolutionary part of their work was demonstrating how traits from totally different
        organisms could be mixed together. They successfully spliced toad DNA into the
        E.coli genome.

       The biotech company, Genentech (founded by Herb Boyer and Robert Swanson)
        announced in 1977 that it had cloned and manufactured the human hormone
        somatostatin using genetic engineering. In 1978 they made another major advance in
        genetic engineering with the production of genetically engineered    by a strain of
                                                                             human insulin


        E. coli.

       In 1981 scientists at Ohio University made a major advance in genetic engineering by
        creating the world's first transgenic animals. They were able to splice rabbit genes into
        the mouse genome, which were passed on to two subsequent mouse generations.

       The Flavr Savr tomato became the first genetically modified plant to be licensed for
        human consumption. It went on the market in 1994 and was only available for a few
        years. The fruit had been genetically engineered to be more resistant to rotting. The
        aim was to produce a crop that could ripen on the vine, but still have a long shelf-life,
        and of course be very tasty.

       Human genetic engineering - in 1990, a four year old girl named Ashanti DeSilva was
        given genetically engineered white blood cells to boost her weak immune system. It
      was the first gene therapy trial, and though the technology is not yet commonplace,
      continued research does make the prospect more likely.

Read more: http://www.brighthub.com/science/genetics/articles/41675.aspx#ixzz0Xta2nfVG
http://www.brighthub.com/science/genetics/articles/41675.aspx
Applications of Genetic Engineering
     Genetic engineering has applications in many fields; medicine, agriculture, the
     environment, and food production. It can be described rather generally as any
     genetic manipulation that allows an organism to perform new functions or produce
     new substances.
 5   The unravelling of DNA and the mapping of a diverse range of organisms such as
     humans, dogs and viruses, is giving us unprecedented knowledge into how nature
     works. Knowing the fundamentals of how a cancer spreads, the tricks a        virus   uses to
     replicate inside our cells, or what prompts a brain to degenerate in Alzheimer's
     patients, equips science with the tools to counter these harsh realities of life.
10   But the technology is not without its critics, and just as genetic engineering has many
     plus points, there are also some cons that must be considered.


     Pros of Genetic Engineering

     In looking at the pros and cons of genetic engineering, we'll consider the technology
     in the fields of agriculture, food production, and medicine.
15   Many crops such as rice, maize, and potatoes are being genetically engineered in
     several ways. Proponents argue that the benefits are many; 1) higher crop yields 2)
     more nutritious food 3) crops can be grown in harsh environments 4) they are more
     resistant to pests thus eliminating the use of potentially hazardous pesticides 5)
     undesirable characteristics can be removed 6) food can have a better flavour and a
20   longer shelf life and 7) they can also be used as a cheap source of medicine.
     To treat many life-threatening illnesses genetic engineering aims to replace faulty
     genes with perfect working copies. The potential is incredible. However, whilst there
     have been some small successes in gene therapy trials to cure vision impairment
     and also X-SCID (where people lack an effective immune system) - it's fair to say that
25   so far the technology hasn't lived up to expectations. It's an extraordinarily difficult job
     to get a gene to exactly where you want it in the body, and for it to function in the way
     that you want it to. Plus our expectations were probably too high from the start.

     Read more: http://www.brighthub.com/science/genetics/articles/15678.aspx#ixzz0XtZBM0S9
30
     Cons of Genetic Engineering

     In terms of gene therapy this can be a dangerous procedure. A virus is being used as
     a vector to get the genes inside, and some fear that even though the virulence
     factors have been silenced, danger is still at hand. There's also a risk that a gene
 5   could land in a spot other than where you want it and cause harm by being
     expressed in unusual ways. There have been several deaths in gene therapy trials,
     most famously that of Jesse Gelsinger in 1999.
     Opposition to the use of genetic engineering in food and agriculture centres on
     several fears. Namely that any gene for herbicide resistance may spread into other
10   crops and create some form of superweed; or that a genetic modification that is
     passed on say through pollination, might pose a hazard to the ecosystem. There's
     also a concern that unusual gene expression may lead to crops causing more allergic
     reactions in consumers.
     There are many more pros and cons of genetic engineering than the few that are
15   listed here, and all are argued passionately by advocates on both sides, many
     clutching reams of data to back up their arguments. That makes it very difficult for the
     lay person to understand exactly what is going on, especially when combatants (if
     that's not too strong a word) seem equally eminent and well qualified.
     What is certain is that even though many are concerned with its speed of
20   introduction, fearing that it is going too fast for society to understand any and all
     possible implications, genetic engineering is here to stay.


     Genetic Engineering and Society

     Of course there are many people who view this kind of genetic manipulation as
     against nature. Proponents of genetic engineering counter this by arguing that man
25   has been manipulating genomes for centuries with the selective breeding of crops
     and cattle. That some see it as against nature is a redundant argument, unless they
     want to go back and live in a cave. Every single technological advance from the pills
     that keep some people alive to the clothes we wear and the vehicles we travel in is
     'against nature.'
30   The advance of technology be it in biotechnology or in computer science is never
     ending. Innovation and finding solutions to problems is what we humans are good at.
     That is not to say that an innovation doesn't of itself present new problems.
     Sometimes it does. However, to stop the progress of technology is against nature,
     human nature. We are born with inquiring minds, we like fixing things; it enhances us
     as a species.
 5   This is not to give carte blanche to scientists and engineers though; innovation
     should never be conducted in a moral vacuum. Society must have every opportunity
     to weigh up the pros and cons. That involves a willingness on the part of scientists to
     explain their work at every opportunity, and in a language that people understand. It
     also requires us the public to listen and to learn for ourselves. Frankly over the years
10   the amount of ill-informed debate about genetics and cloning has been ridiculous.
     Some of the blame goes to the media who love to make up stories about the 'evil
     geniuses' wanting to create Frankenstein's monster.
     Genetic engineering is a valuable technology, but it is not without its faults and
     technical difficulties. There is also no such thing as absolute safety or zero risk. Every
15   new technology has some risk attached to it. As long as the benefits far outweigh any
     negative effects, and that everything possible is done to ensure that those risks are
     minimal, new technologies, including genetic engineering should be pursued with
     vigour. The biggest risk may be in not pursuing them?
http://www.brighthub.com/science/genetics/articles/15678.aspx

				
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