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					                          Examples of GM Food

    Are these claims supported by evidence?


    Let’s take a look into
    some examples of GM
    food!


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Example 1: GM maize
    About 7% of the world‟s maize (sweet corn) production is
    lost to a pest called the European corn borer.




    The larvae live inside the maize stalk.
    Pest control is not efficient. Large amounts of pesticides are
    used.
    The cost of growing maize increases.

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              causes losses to




    farmers     the environment   the economy
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    A gene extracted from a soil bacterium is inserted
    into maize
                     The GM maize can produce a
                     protein called Bt protein.

                                    Bt protein




                       When the corn borer larvae eat
                       this protein, their intestinal walls
                       are damaged, causing them to
                       die of starvation.
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                     GM
                                 benefits




The cost is lowered, the                             Less maize is lost.
                           Less pesticide is used.
 crop yield increases.


      Consumers get better quality and more maize

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Example 2: GM rice
       GM rice has a higher crop yield (greater
        weight of rice per plant).

       Who benefits?
        Farmers, consumers, economy




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   Rice is the main carbohydrate source in many
    countries.

   GM rice increases food supply thus may
    reduce food shortage.

   Who benefits?
    People suffering from hunger or in poverty
    (rice may be cheaper)



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                 Golden rice

       A new GM rice – golden rice,
         – rich in pro-vitamin A (a precursor of vitamin A)

       People in developing countries suffer from vitamin A
        deficiency leading to blindness

       Golden rice may solve the problem of vitamin A
        deficiency in developing countries.


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A protein in a new variety of GM rice (Bt rice) may
cause allergy in humans (NB: this is NOT “golden rice”)



    Are GM foods safe enough?



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    GM foods are supposed to be assessed by each
     different country before it is allowed onto the market
     there

    GM foods are usually tested for their toxicity and
     whether or not they cause allergy

    Approved GM foods are therefore not likely to cause
     risks to human health




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     But…..
        The first GM food was marketed only in 1994.
          – Long term effects on human health cannot yet be
            assessed.
           Laboratory animals don‟t live as long as humans do


        Animal tests can‟t pick up small effects on intelligence
         or personality (brain functions)

        Trials for food safety of GM crops are often carried
         out by the companies that have developed them, not
         by independent researchers.


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 Moreover….
     Some GM food have antibiotic-
     resistant marker genes
                   Why?
     The desirable gene may be transferred
     WITH an antibiotic-resistance gene.
     By testing the modified organisms with
     antibiotics, scientists can tell whether the
     desired gene has been successfully
     inserted into the “new” organism.




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Some GM food have antibiotic-
resistant marker genes…



      What is the risk?

The marker genes may be transferred to
other pathogens which become resistant,
antibiotics will no longer be effective in
treating diseases.

This may lead to development of “super
pests”



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      Does GM food really benefit farmers and
      consumers?
     GM crops are mainly developed by a few large
     biotechnology companies

     The companies have patents on the GM crops genome


      Do the farmers need to pay extra to buy GM
                       seeds?

       The cost may be higher because the seeds
                 are more expensive
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Potential risks to the environment?
     Genes from GM crops might escape, through pollen, to
     weeds which are relatives of the crops.

        i.e. the genes may escape into the wild.


     GM crops may be toxic to some insects that eat them.

     Dead or dying insects may be eaten by birds.

     The birds may die because of the toxic effect.

     This may lead to extinction of some species of
     insects or birds.
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    All organisms are interrelated. Changes in one species
     may have unpredictable consequences in other parts
     of an ecosystem.

  GM crops may grow and reproduce faster.
  They may out-compete other plants in an ecosystem.




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Ethical problems?
    Do we have a right to alter ANY
     genetic material?

    Is genetic engineering
     unnatural?

    Is genetic engineering „playing
     God‟?


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posted:8/11/2011
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