Генетически модифицированная пища и клонирование 
Генетически модифицированная пища и клонирование
I. Introduction.
I have chosen this
problem because I am extremely interested in biology, ecology and the history
of mankind. The problem of genetic modification and cloning is very important
at the present time. The theme of genetically modified food is actual as every
year it takes the greater place in our diet. Many scientists declare danger of
the use of genetically modified food stuffs to health. They warn that
consumption of similar products is capable to lead to unpredictable
consequences, including mutations. One of big problems of a condition in that area
is that genetic engineering is being moved by extreme commercial interests. The
biotechnological companies aspire to patent and deduce on the market all new products
and new genetically modified organisms (plants and animals), not caring about
what collateral consequences genetic changes can have.
To please commercial
interests of some huge companies any precaution is rejected: in fact being
guided by only scientific approach, it would be necessary to test some
generations of plants to be convinced of their safety. It has not been made in
a case with modified plants as process of testing can borrow millennia. In my work I will try to describe
the positive and negative features of genetic engineering, having resulted
possible reasons and examples. In fact now there is a set of disputes and
discussions so even the urgency of this theme is proved by a simple example -
quantity of existing films and serials about this problem.
Genetically modified products
can be toxic and dangerous for people. In 1989 the modification of
L-Tryptophan, the food additive, caused death of 37 Americans and made invalids
5000 persons because of causing sufferings and potentially fatal illness of
blood. Only after that event the product has been withdrawn from the use. According
to special explorations, genetically modified L-Tryptophan was equivalent to previous
substances which were made with the help of bacteria of natural type. However it did not correspond to these preparations on parameters of
safety. If other tests had been carried out, for example, the test for assimilation
by animals and people, the fact that this product was not safe would have become
obvious. But such tests had not been carried out.
People have different points of view
about whether the genetic modification of food is a good thing – in fact it is
quite a controversial topic. Those involved in the biotechnology business
insist it is safe and that genetic modification can increase yields, reduce waste
and improve the flavour and keeping qualities of products. For example, soft
fruits can be made firmer to prevent spoilage during transportation. People in
favour of genetic modification also say that better use can be made of
agricultural land as crops can potentially be modified to grow in hostile
conditions, such as those of a drought; this will help in feeding the world.
The later is a vital issue. The same goes for improving the nutritional value
of foods. More than 800 million people still go hungry, and 82 countries (half
of them in Africa) neither grow enough food, nor can afford to import it. In
India alone, 85% of children under five live below the normal, acceptable state
of nutrition.
It is well known that the
fear of new and unknown things is a peculiar feature of people. People have
already forgotten that a few dozens of years ago the world was shocked by the discussion
about an opportunity of cloning of human beings. This opportunity appeared after
the successful cloning of frogs.
Several years ago the
mankind was shocked by reports in mass media about Dolly the Scottish sheep,
which was represented as its founders assert, an exact copy of its genetic
mother. American bull Jefferson and the bull, deduced by the French biologists
appeared later. The prospect of work on cloning of a human being is publicly
discussed.
Cloning of bodies and
fabrics is the problem number one in the field of transplantology, traumatology
and in other areas of medicine and biology. Cloned bodies become a kind of rescue
for people who have got in automobile failures or any other accidents or for
people who need radical help because of diseases caused by age.
The latest months
enabled experts to comprehend soberly the situation, to estimate some methodical
and technological difficulties lying in the field of mammal cloning. Cloning of
a human being can create unsuccessful copies, ugly creatures, but all humankind
will be responsible for his or her ugliness. Opponents of female equality and feminism assure that men
will not be necessary if cloning is developed. It is absolutely incorrect from
the biological and social points of view. Women were compelled to live without men
who had not come back from wars. Hardly it was useful to somebody. And hardly
women will be always able to do without man's sexual cells for continuation of
future generations.
So first of all we shall
try not to fear of new and unknown things. And we shall recollect that cloning
constantly occurs in natural conditions when identical twins are born. They are
identical in their genetic set. It can be easily proved by an opportunity of
changing body parts and fabrics between them. Thus, emotional objections
against cloning of people have no rational base.
I would like to be a
scientist and carry out the experiments of cloning parts of human body. I am
absolutely sure that nobody can clone a person because it is not a biological
object, but it is the result of socializing, communication, background
mentality, language etc.
II.
The Main Body.
Genetically
modified food.
What is genetic modification?
Unlike normal methods of
reproduction, genetic modification is done in the laboratory by cutting,
joining and transferring genes between totally unrelated living things. As a
result, combinations of genes which would never occur naturally are produced.
Everyone has heard of Dolly the
sheep and experiments in the medial field, but genetic modification is also
happening in the food industry. It is possible to isolate and transfer
different characteristics between unrelated species or between plants and
animals. For example, the introduction of an “anti-freeze” gene from an Arctic
fish into tomatoes or strawberries made them resistant to frost.
Around 40% of the world’s total crop
production is lost to pests and diseases, despite the heavy use of pest-killing
chemicals. Cauliflowers are no exception, and suffer damage from aphids and
other insects. Scientists have looked to nature to find a solution to this
problem and discovered that snowdrops are able to survive attacks from some of
the most devastating pests. Snowdrops produce a substance called lectin, which
affects insects by interfering with their digestive systems. The task is to
transfer the gene for lectin production, and thus the property of insect resistance,
into cauliflowers.
It is known that tomatoes, carrots
and peppers are rich in carotenoids, which help prevent cancer ant coronary
heart disease. To make things easier for us, scientists are working to produce
vegetables that are genetically modified to contain increased carotenoid
levels. They have already succeeded in creating tomatoes with more than three
times the normal “anti-cancer” power.
Animals can also be “engineered”.
When salmon were modified with the gene for cold resistance from the flounder
fish, they grew 10 times as fast as normal salmon because the inserted gene had
interfered with their grown harmone gene. A pig was modified with a human gene
to make it grow faster and leaner. But these efforts have resulted in numerous
problems and serious diseases among the experimental animals. [6]
Genetic modification can save the
world.
People have different points of view
about whether the genetic modification of food is a good thing – in fact it is
quite a controversial topic. Those involved in the biotechnology business
insist it is safe and that genetic modification can increase yields, reduce
waste and improve the flavour and keeping qualities of products. For example,
soft fruits can be made firmer to prevent spoilage during transportation.
People in favour of genetic modification also say that better use can be made
of agricultural land as crops can potentially be modified to grow in hostile
conditions, such as those of a drought; this will help in feeding the world.
The later is a vital issue. The same goes for improving the nutritional value
of foods. More than 800 million people still go hungry, and 82 countries (half
of them in Africa) neither grow enough food, nor can afford to import it. In
India alone, 85% of children under five live below the normal, acceptable state
of nutrition.
Many, if not all Southern countries,
posses the indigenous genetic resources – requiring no further genetic
modification – that can guarantee a sustainable food supply. For instance, in a
single village of northeast India, 70 varieties of rice are grown… Farmers
repeatedly used and enchanted some varieties that were resistant to disease,
drought and flood, some that tasted nice, some that were coloured and useful
for ritual purposes and some that were highly productive. It seems obvious that
there is no need for genetically modified crops. On the contrary, they will
undermine food security and biodiversity. The best thing is to sustain existing
indigenous agricultural diversity as the basis of a secure and nutritious food
base for all. [6]
Genetic modification can be
dangerous and unpredictable.
But on the other hand, many
professional independent observers believe genetic engineering is unpredictable
and dangerous. They think that the risks are not worth taking, especially since
they are not safe. This science is too new to guarantee that problems will not
occur in the future. When moved from one species to another, genes can create
new unknown dangers. Small changes could have big impacts. Once released into
the natural environment, genetically modified plants interbreed with those in
the wild. The spread of modified genes from one organism to another in the wild
is technically termed “a gene flow”. It has already led to the creation of new
strains of “super weeds” that are resistant to herbicides. Perhaps most
worrying of all, there is no way of recalling a genetic modification. Once
released into the environment, genetic pollution cannot be cleaned up; it will
survive so long as there is life on Earth. The environment will be irreversibly
altered. Natural plants and animals could be driven out.
Mistakes have already been made in
genetic engineering. Use of genetically modified bacteria in the food
supplement Tryptophan may have caused 37 deaths in the USA since 1989 as well
as permanently disabling thousands of people.
A company called Pioneer Hi-Bred
developed a variety of genetically modified soya spliced with a Brazil nut gene
to increase its protein content. When it was discovered that individuals allergic
to Brazil nuts also reacted to the modified soya, the company had to withdraw
the product.
In a 1994 field test, natural
potatoes were planted at a distance of up to 1,100 metres from a batch of
genetically modified potatoes. When seeds from the unmodified potatoes were
later collected, it was found that 72% of the natural plants grown near the
modified batch had absorbed the modified gene, and 35% of those grown further
away had also done so. In another study in the same year, scientists at the
Scottish Crop Research Institute found that pollen from genetically modified
rapeseed had fertilized plants up to 2.5 kilometers away.
The company Ciba Geigy PLC recently
introduced genetically modified maize, which is altered to be resistant to a
herbicide and contains a marker gene for resistance to the widely used
antibiotic ampicillin. Microorganisms in the stomach could absorb the gene for
resistance to the antibiotic and spread into the environment, leaving a vita
medical resource useless. The European Parliament expresses fear that
consumption of the maize might weaken the effect of some antibiotic medicines
in the human body. And the finite risk could be absolutely catastrophic if it
occurred.
A soil bacterium was modified to
break down a particular herbicide. It did so, but the unexpected end result was
a substance highly toxic to vital soil fungi, which were destroyed.
Now just twenty-odd years since this
was discovered, experiments have produced genetically modified types of most
major food crops and these have recently started to be given legal approval
despite opposition from thousands of organizations who have high lighted the
dangers, and without informed public debate. A report by 100 US scientists
suggested that genetically modified organisms could cause “… irreversible,
devastating damage to the technology”. British scientists have also spoken out
– Dr. Michael Antoniou, a senior molecular biologist who has experience in
conducting genetic engineering experiments in the laboratory said: “This is an
imperfect technology with inherent dangers”. The Prince of Wales also speaks
out about genetic foods. He urges scientists to stop playing God by tinkering
with food. He says there is no way of knowing the long-term consequences of
producing and eating genetically modified crops, and points to the “man-made”
BSE[1]
disaster an example of the dangers of the quest for cheap food. The Prince says
that genetic engineering “takes mankind into realms that belong to ‘God and to
God alone’, “and raises ethical and practical considerations. “Apart from
certain highly-beneficial and specific medical applications, do we have the
right to experiment with and commercialize the building blocks of life? We live
in an age of rights – and it seems that it is time that our Creator had some
rights too.” Later, an article from The Daily Telegraph continues, “We
simply do not know the long-term consequences for human health and the wider
environment of releasing plants bred in this way … The lesson of BSE[1] and other entirely man-made
disasters on the road to “cheap food” is surely the greatest cause for concern.
Even the best science cannot predict the unpredictable.”
The author of a report on genetic
engineering from Brussels, Doug Parr, says, “It’s like the genie in bottle: once
it’s out, you cannot put it back. Already there are too many cases of things
going wrong.”
Susan Leubuscher of Green Pease’s
European Unit in Brussels says, “The science of genetic engineering is
unpredictable, but few, from scientists to governments, dare raise the fact
that today’s Golden Goose of industry is laying some rotten eggs.” [6]
The problems of labeling genetically
modified food.
Do not be surprised if you have not
heard much about genetically modified foods, because neither the chemical companies
who produce them nor the governments are exactly running public information
campaigns about them. Agricultural biotechnology is big business, and science
has been absorbed into industry to an unprecedented extent. Practically all
established molecular geneticists have some industrial ties, thus limiting
what they can do research on particularly with regard to safely. The
transnational companies will soon be in a position to dictate the future of the
food industry. And they know just how they want our food to be produced – in
ways that will maximize their own profits. That means using the gene technology
which they have patented and can control, despite the risk of irreversible
global consequences for the rest of us.
Some of the food companies are refusing
to segregate crops which contain modified genes from those which do not. This
makes it impossible to have a proper labeling scheme, which would allow people
to make up their minds about weather or not they should eat the products of
gene technology. Only a few genetically modified products are on sale in the
supermarkets of Great Britain at the moment. Unfortunately, the situation is
changing because of the soya bean. Soya beans are grown mainly in North America
and find their way into 60% of all processed foods. For example they are in
bread, biscuits, baby foods, chocolate, ice cream and many vegetarian products.
The inclusion of soya makes it more than likely that people in Britain are
already eating modified soya, whether they like it or not. Monsanto , a giant
chemical company, modified a soya bean with genetic material from a virus and a
petunia linked to a bacterial gene, which has made the soya plant resistant to
a weed-killer called Roundup, which is also manufactured by Monsanto. Companies
like Monsanto do not spend millions on a new soya bean because it will feed the
poor and starving. They believe it will make their shareholders fabulously
wealthy. Farmers have to sign restrictive contracts promising to use Monsanto’s
weed-killers and not grow their own seed. In the race to spread their modified
crops all over the world, little attention is being paid to the dangers.
Perhaps it is the danger to human health that it most worrying. As our food
becomes more and more refined and synthetic, its nutritional value falls, and
unexpected health effects are continually surfacing. Some of these do not
appear for years, even decades, after the food was eaten. At the same time,
unchanged, unprocessed, natural food may actually become more expensive and harder
to find. Even when toxins aren’t produced, allergies can be triggered
unexpectedly. [6]
There is one more thing that comes
into question – is it ethical to move genes around? Introducing genes from
bacteria, viruses and even animals into plants raises serious concerns for many
people, in particular vegetarians and those with certain religious beliefs.
Cloning.
A huge quantity of
disputes and discussions concerning cloning are carried out nowadays. It is well known that the fear of new
and unknown things is a peculiar feature of people. People have already
forgotten that a few dozens of years ago the world was shocked by the
discussion about an opportunity of cloning of a human being. This opportunity
has appeared after successful cloning of frogs.
Several years ago, the
humankind was shocked by reports in mass media about Dolly the Scottish sheep,
which was represented as its founders assert, an exact copy of its genetic
mother. American bull Jefferson and the bull, deduced by the French biologists
appeared later. The prospect of work on cloning of a human being is publicly
discussed.
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