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Genetic Engineering

All that we are is the result of what we have thought
                                                                      Buddha

                            For what shall it profit a man, if he shall gain
                                      the whole world and lose his own soul?
                                                                   The Bible


Introduction

While plant biotechnology has been used for centuries to enhance plants,
microorganisms and animals for food, only recently has it allowed for the
transfer of genes from one organism to another. Yet there is now a
widespread controversy over the harmful and beneficial effects of genetic
engineering to which, at this time, there seems to be no concrete solution.
The ideas below are expected to bring in a bit of clearance into the topic.
Here Im going to reveal some facts concerning genetic engineering,
specially the technology, its weak and strong points (if any). Probably the
information brought is a bit too prejudiced, for Im certainly not in favor
of making jokes with nature, but I really tried to find some good things
about GE.



What is genetic engineering?


Genetic engineering is a laboratory technique used by scientists to change
the DNA of living organisms.
DNA is the blueprint for the individuality of an organism. The organism
relies upon the information stored in its DNA for the management of every
biochemical process. The life, growth and unique features of the organism
depend on its DNA. The segments of DNA which have been associated with
specific features or functions of an organism are called genes.
Molecular biologists have discovered many enzymes which change the
structure of DNA in living organisms. Some of these enzymes can cut and
join strands of DNA. Using such enzymes, scientists learned to cut specific
genes from DNA and to build customized DNA using these genes. They also
learned about vectors, strands of DNA such as viruses, which can infect a
cell and insert themselves into its DNA.
With this knowledge, scientists started to build vectors which incorporated
genes of their choosing and used the new vectors to insert these genes into
the DNA of living organisms. Genetic engineers believe they can improve the
foods we eat by doing this. For example, tomatoes are sensitive to frost.
This shortens their growing season. Fish, on the other hand, survive in
very cold water. Scientists identified a particular gene which enables a
flounder to resist cold and used the technology of genetic engineering to
insert this 'anti-freeze' gene into a tomato. This makes it possible to
extend the growing season of the tomato.
At first glance, this might look exciting to some people. Deeper
consideration reveals serious dangers.


Techniques

There are 4 types of genetic engineering which consist of recombinant
engineering, microinjection, electro and chemical poration, and also
bioballistics.


r-DNA technology

The first of the 4, recombinant engineering, is also known as r-DNA
technology. This technology relies on biological vectors such as plasmids
and viruses to carry foreign genes into cells. The plasmids are small
circular pieces of genetic material found in bacteria that can cross
species boundaries. These circular pieces can be broken, which results with
an addition of a new genetic material to the broken plasmids. The plasmids,
now joined with the new genetic material, can move across microbial cell
boundaries and place the new genetic material next to the bacterium's own
genes. After this takes place, the bacteria will then take up the gene and
will begin to produce the protein for which the gene codes. In this
technique, the viruses also act as vectors. They are infectious particles
that contain genetic material to which a new gene can be added. Viruses
carry the new gene into a recipient cell driving the process of infecting
that cell. However, the viruses can be disabled so that when it carries a
new gene into a cell, it cannot make the cell reproduce or make copies of
the virus.


Microinjection

The next type of genetic engineering is referred to as microinjection. This
technique does not rely on biological vectors, as does r-DNA. It is
somewhat of a simple process. It is the injecting of genetic material
containing the new gene into the recipient cell. Where the cell is large
enough, injection can be done with a fine-tipped glass needle. The injected
genes find the host cell genes and incorporate themselves among them.


Electro and chemical poration

This technique is a direct gene transfer involving creating pores or holes
in the cell membrane to allow entry of the new genes. If it is done by
bathing cells in solutions of special chemicals, then it is referred to as
chemical poration. However, if it goes through subjecting cells to a weak
electric current, it is called electroporation.


Bio ballistics

This last technique is a projectile method using metal slivers to deliver
the genetic material to the interior of the cell. These small slivers,
which must be smaller than the diameter of the target cell, are coated with
genetic material. The coated slivers are propelled into the cells using a
shotgun. After this has been done, a perforated metal plate stops the shell
cartridge but still allows the slivers to pass through and into living
cells on the other side. Once inside, the genetic material is transported
to the nucleus where it is incorporated among host cells.


The history of GE

The concept was first introduced by an Australian monk named Gregor Mendel
in the 19th century. His many experiments cemented a foundation for future
scientists and for the founding concepts in the study of genetics.
Throughout Mendel's life, he was a victim of criticism and ridicule by his
fellow monks for his "foolish" experiments. It took 35 years until he was
recognized for his experiments and known for the selective breeding
process. Mendel's discoveries made scientists wonder how information was
transferred from parent to offspring and whether the information could be
captured and/or manipulated.
James D. Watson and Francis H. C. Crick were curious scientists who later
became known as the founding fathers of genetic engineering.
Watson and Crick wanted to determine how genetic blueprints are determined
and they also proposed that DNA structures are genetic messengers or that
chemical compounds of proteins and amino acids all come together as a way
to rule out characteristics and traits. These 2 scientists produced a code
of DNA and thus answered the question of how characteristics are
determined. They also established that DNA are the building blocks of all
organisms.


Selective breeding and genetic engineering

Selective breeding and genetic engineering are "both used for the
improvement of human society." However, selective breeding is a much longer
and more expensive process than genetic engineering. It takes genetic
engineering only one generation of offspring to see and study improvement
as opposed to selective breeding where many generations are necessary.
Therefore, it costs more to observe many generations.
Selective breeding is known as the natural way to engineer genes while
genetic engineering is more advanced, technical, scientific, complex and is
inevitable in out future.



What are the dangers?

Many previous technologies have proved to have  adverse  effects  unexpected
by their developers. DDT, for example, turned out to accumulate in fish  and
thin  the  shells  of  fish-eating  birds  like  eagles  and  ospreys.   And
chlorofluorocarbons turned out  to  float  into  the  upper  atmosphere  and
destroy ozone, a chemical that shields the earth from  dangerous  radiation.
What harmful effects might turn  out  to  be  associated  with  the  use  or
release of genetically engineered organisms?
This  is  not  an  easy  question.  Being  able  to  answer  it  depends  on
understanding complex biological and ecological systems. So far,  scientists
know of no generic harms associated with genetically  engineered  organisms.
For example, it is not true that all genetically engineered foods are  toxic
or that all released engineered organisms are likely to proliferate  in  the
environment. But specific engineered organisms may be harmful by  virtue  of
the novel gene combinations they possess.  This  means  that  the  risks  of
genetically engineered organisms must be assessed  case  by  case  and  that
these risks  can  differ  greatly  from  one  gene-organism  combination  to
another.
So far, scientists have identified a number of  ways  in  which  genetically
engineered organisms could potentially adversely impact  both  human  health
and the environment. Once the potential harms are identified,  the  question
becomes how likely are they to occur. The  answer  to  this  question  falls
into the arena of risk assessment.
In addition to posing risks of harm that we  can  envision  and  attempt  to
assess, genetic engineering may also pose risks that we simply do  not  know
enough to identify. The recognition of this possibility does not  by  itself
justify stopping the technology, but does put a substantial burden on  those
who wish to go forward to demonstrate benefits.



Fundamental Weaknesses of the Concept


Imprecise TechnologyA genetic engineer moves genes from one organism to
another. A gene can be cut precisely from the DNA of an organism, but the
insertion into the DNA of the target organism is basically random. As a
consequence, there is a risk that it may disrupt the functioning of other
genes essential to the life of that organism. (Bergelson 1998)

Side EffectsGenetic engineering is like performing heart surgery with a
shovel. Scientists do not yet understand living systems completely enough
to perform DNA surgery without creating mutations which could be harmful to
the environment and our health. They are experimenting with very delicate,
yet powerful forces of nature, without full knowledge of the repercussions.
(Washington Times 1997)

Widespread Crop FailureGenetic engineers intend to profit by patenting
genetically engineered seeds. This means that, when a farmer plants
genetically engineered seeds, all the seeds have identical genetic
structure. As a result, if a fungus, a virus, or a pest develops which can
attack this particular crop, there could be widespread crop failure.
(Robinson 1996)

Threatens Our Entire Food SupplyInsects, birds, and wind can carry
genetically altered seeds into neighboring fields and beyond. Pollen from
transgenic plants can cross-pollinate with genetically natural crops and
wild relatives. All crops, organic and non-organic, are vulnerable to
contamination from cross-pollinatation. (Emberlin 1999)



Health Hazards

Here are the some examples of the potential adverse effects  of  genetically
engineered organisms may have on human health. Most of  these  examples  are
associated with the growth and consumption of genetically engineered  crops.
Different risks would be  associated  with  genetically  engineered  animals
and, like the risks associated with plants, would depend largely on the  new
traits introduced into the organism.



New Allergens in the Food Supply

Transgenic crops  could  bring  new  allergens  into  foods  that  sensitive
individuals would not know to avoid. An example  is  transferring  the  gene
for one of the many allergenic proteins found in milk into  vegetables  like
carrots. Mothers who know to avoid  giving  their  sensitive  children  milk
would not know to avoid  giving  them  transgenic  carrots  containing  milk
proteins. The problem is unique to genetic engineering because it alone  can
transfer  proteins  across  species  boundaries  into  completely  unrelated
organisms.
Genetic engineering routinely moves  proteins  into  the  food  supply  from
organisms that have never been consumed as foods.  Some  of  those  proteins
could be food allergens,  since  virtually  all  known  food  allergens  are
proteins. Recent research substantiates concerns about  genetic  engineering
rendering previously safe foods allergenic. A study  by  scientists  at  the
University  of  Nebraska  shows  that  soybeans  genetically  engineered  to
contain Brazil-nut proteins  cause  reactions  in  individuals  allergic  to
Brazil nuts.
Scientists have limited ability to  predict  whether  a  particular  protein
will be a food allergen, if  consumed  by  humans.  The  only  sure  way  to
determine whether protein will be an allergen is  through  experience.  Thus
importing proteins, particularly from nonfood  sources,  is  a  gamble  with
respect to their allergenicity.



Antibiotic Resistance

Genetic  engineering  often  uses  genes  for   antibiotic   resistance   as
"selectable markers." Early in the engineering process, these  markers  help
select cells that have  taken  up  foreign  genes.  Although  they  have  no
further use, the genes continue to  be  expressed  in  plant  tissues.  Most
genetically engineered  plant  foods  carry  fully  functioning  antibiotic-
resistance genes.
The presence of antibiotic-resistance genes in foods could have two  harmful
effects. First,  eating  these  foods  could  reduce  the  effectiveness  of
antibiotics to fight disease when these antibiotics are  taken  with  meals.
Antibiotic-resistance genes produce enzymes that  can  degrade  antibiotics.
If a tomato with an antibiotic-resistance gene is eaten at the same time  as
an antibiotic, it could destroy the antibiotic in the stomach.
Second, the resistance  genes  could  be  transferred  to  human  or  animal
pathogens, making them  impervious  to  antibiotics.  If  transfer  were  to
occur, it could aggravate the already serious health problem of  antibiotic-
resistant  disease  organisms.  Although  unmediated  transfers  of  genetic
material from plants to bacteria are highly unlikely, any  possibility  that
they may occur requires careful scrutiny in  light  of  the  seriousness  of
antibiotic resistance.
In addition, the  widespread  presence  of  antibiotic-resistance  genes  in
engineered food suggests  that  as  the  number  of  genetically  engineered
products grows, the effects of  antibiotic  resistance  should  be  analyzed
cumulatively across the food supply.



Production of New Toxins

Many organisms have the ability to produce  toxic  substances.  For  plants,
such substances help to defend stationary organisms from the many  predators
in their environment.  In  some  cases,  plants  contain  inactive  pathways
leading to toxic  substances.  Addition  of  new  genetic  material  through
genetic engineering could reactivate these inactive  pathways  or  otherwise
increase the levels of  toxic  substances  within  the  plants.  This  could
happen, for example, if the on/off signals associated  with  the  introduced
gene were located on the genome in places  where  they  could  turn  on  the
previously inactive genes.



Concentration of Toxic Metals

Some of the new genes being added to crops  can  remove  heavy  metals  like
mercury from the soil and concentrate them in the plant tissue. The  purpose
of creating such crops is to make possible the use of  municipal  sludge  as
fertilizer. Sludge contains useful plant  nutrients,  but  often  cannot  be
used as fertilizer because it is contaminated with toxic heavy  metals.  The
idea is to engineer plants to remove and sequester those metals in  inedible
parts of plants. In a tomato, for example, the metals would  be  sequestered
in the roots; in potatoes in the leaves. Turning on the genes in  only  some
parts of the plants requires the use of genetic on/off  switches  that  turn
on only in specific tissues, like leaves.
Such products pose risks of contaminating foods with high  levels  of  toxic
metals if the on/off switches  are  not  completely  turned  off  in  edible
tissues. There are also environmental risks  associated  with  the  handling
and disposal of the metal-contaminated parts of plants after harvesting.



Enhancement of the Environment for Toxic Fungi

Although for the most part health  risks  are  the  result  of  the  genetic
material newly added to organisms, it is also possible for  the  removal  of
genes and gene products to cause problems. For example, genetic  engineering
might be used to produce decaffeinated coffee beans by deleting  or  turning
off genes associated with caffeine production. But  caffeine  helps  protect
coffee beans against fungi. Beans that are unable to produce caffeine  might
be coated with fungi, which can  produce  toxins.  Fungal  toxins,  such  as
aflatoxin, are potent human toxins that can remain active through  processes
of food preparation.

No Long-Term Safety Testing
Genetic engineering uses material from organisms that have never been part
of the human food supply to change the fundamental nature of the food we
eat. Without long-term testing no one knows if these foods are safe.



Decreased Nutritional Value

Transgenic foods may mislead consumers with counterfeit freshness. A
luscious-looking, bright red genetically engineered tomato could be several
weeks old and of little nutritional worth.
Problems Cannot Be Traced
Without labels, our public health agencies are powerless to trace problems
of any kind back to their source. The potential for tragedy is staggering.


Side Effects can Kill

37 people died, 1500 were partially paralyzed, and 5000 more were
temporarily disabled by a syndrome that was finally linked to tryptophan
made by genetically-engineered bacteria.



Unknown Harms

As with any new technology, the full set of risks  associated  with  genetic
engineering have almost  certainly  not  been  identified.  The  ability  to
imagine what might go wrong with a technology is limited  by  the  currently
incomplete understanding of physiology, genetics, and nutrition.



Potential Environmental Harms



Increased Weediness

One way of thinking generally about the environmental harm that  genetically
engineered plants might do is to consider  that  they  might  become  weeds.
Here, weeds means all plants in places where humans do not  want  them.  The
term covers everything from Johnson grass choking crops in fields  to  kudzu
blanketing trees to melaleuca trees invading the Everglades. In  each  case,
the plants are growing unaided by humans in places  where  they  are  having
unwanted effects. In agriculture, weeds can severely inhibit crop yield.  In
unmanaged environments, like the Everglades,  invading  trees  can  displace
natural flora and upset whole ecosystems.
Some weeds result from the accidental  introduction  of  alien  plants,  but
many were the  result  of  purposeful  introductions  for  agricultural  and
horticultural purposes. Some of the  plants  intentionally  introduced  into
the United  States  that  have  become  serious  weeds  are  Johnson  grass,
multiflora rose, and kudzu. A  new  combination  of  traits  produced  as  a
result of genetic engineering might enable crops to thrive  unaided  in  the
environment in circumstances where they would  then  be  considered  new  or
worse weeds. One example would be  a  rice  plant  engineered  to  be  salt-
tolerant that escaped cultivation and invaded nearby marine estuaries.



Gene Transfer to Wild or Weedy Relatives

Novel genes placed in  crops  will  not  necessarily  stay  in  agricultural
fields. If relatives of the altered crops are growing near  the  field,  the
new gene can easily move via pollen into those plants. The new traits  might
confer on wild or weedy relatives of crop plants the ability  to  thrive  in
unwanted places, making them weeds as defined above.  For  example,  a  gene
changing the oil  composition  of  a  crop  might  move  into  nearby  weedy
relatives in which the  new  oil  composition  would  enable  the  seeds  to
survive the winter. Overwintering might allow the plant to become a weed  or
might intensify weedy properties it already possesses.



Change in Herbicide Use Patterns

Crops genetically engineered to be  resistant  to  chemical  herbicides  are
tightly linked to the use of particular  chemical  pesticides.  Adoption  of
these crops  could  therefore  lead  to  changes  in  the  mix  of  chemical
herbicides used across the country. To the extent that  chemical  herbicides
differ in  their  environmental  toxicity,  these  changing  patterns  could
result in  greater  levels  of  environmental  harm  overall.  In  addition,
widespread  use  of  herbicide-tolerant  crops  could  lead  to  the   rapid
evolution of resistance to herbicides  in  weeds,  either  as  a  result  of
increased exposure to the herbicide or as a result of the  transfer  of  the
herbicide trait to weedy relatives of crops. Again, since herbicides  differ
in their environmental harm, loss of some herbicides may be  detrimental  to
the environment overall.



Squandering of Valuable Pest Susceptibility Genes

Many insects contain genes  that  render  them  susceptible  to  pesticides.
Often these susceptibility  genes  predominate  in  natural  populations  of
insects. These genes are a valuable  natural  resource  because  they  allow
pesticides to remain as effective pest-control tools. The  more  benign  the
pesticide, the more valuable the genes that make pests susceptible to it.
Certain genetically engineered crops threaten the  continued  susceptibility
of  pests  to  one  of  nature's  most  valuable  pesticides:  the  Bacillus
thuringiensis or Bt toxin. These "Bt crops" are  genetically  engineered  to
contain a gene for the Bt toxin. Because the  crops  produce  the  toxin  in
most plant tissues throughout  the  life  cycle  of  the  plant,  pests  are
constantly exposed to it. This continuous  exposure  selects  for  the  rare
resistance genes in the pest population and  in  time  will  render  the  Bt
pesticide useless, unless specific measures  are  instituted  to  avoid  the
development of such resistance.



Poisoned Wildlife

Addition of foreign genes to plants could  also  have  serious  consequences
for wildlife in a number of circumstances.  For  example,  engineering  crop
plants, such as tobacco or rice,  to  produce  plastics  or  pharmaceuticals
could endanger mice or deer who consume  crop  debris  left  in  the  fields
after  harvesting.  Fish  that  have  been  engineered  to  contain   metal-
sequestering proteins (such fish have been  suggested  as  living  pollution
clean-up devices) could be harmful if consumed by other fish or raccoons.



Creation of New or Worse Viruses

One  of  the  most  common  applications  of  genetic  engineering  is   the
production of virus-tolerant crops. Such crops are produced  by  engineering
components  of  viruses  into  the  plant  genomes.  For  reasons  not  well
understood, plants producing viral components on their own are resistant  to
subsequent infection by those viruses.  Such  plants,  however,  pose  other
risks  of  creating  new  or   worse   viruses   through   two   mechanisms:
recombination and transcapsidation.
Recombination can occur between the plant-produced viral genes  and  closely
related genes of incoming viruses. Such recombination  may  produce  viruses
that can infect a wider range of hosts or that may  be  more  virulent  than
the parent viruses.
Transcapsidation involves the encapsulation of the genetic material  of  one
virus by the  plant-produced  viral  proteins.  Such  hybrid  viruses  could
transfer viral genetic material to a  new  host  plant  that  it  could  not
otherwise infect. Except in rare circumstances, this would  be  a  one-time-
only effect, because the viral genetic material carries  no  genes  for  the
foreign proteins within which it was encapsulated and would not be  able  to
produce a second generation of hybrid viruses.


Gene Pollution Cannot Be Cleaned Up

Once genetically engineered organisms, bacteria and viruses are released
into the environment it is impossible to contain or recall them.
Unlike chemical or nuclear contamination, negative effects are
irreversible.


DNA is actually not well understood.

Yet the biotech companies have already planted millions of acres with
genetically engineered crops, and they intend to engineer every crop in the
world.
The concerns above arise from an appreciation of the fundamental role DNA
plays in life, the gaps in our understanding of it, and the vast scale of
application of the little we do know. Even the scientists in the Food and
Drug administration have expressed concerns.



Unknown Harms

As with human health risks, it is unlikely that all potential harms  to  the
environment have been identified. Each of the potential harms  above  is  an
answer to the question, "Well, what might go  wrong?"  The  answer  to  that
question depends on how well scientists  understand  the  organism  and  the
environment into which it is released. At this point,  biology  and  ecology
are too poorly understood to be certain  that  question  has  been  answered
comprehensively.



Any pros?

Certainly, there should be some. Still, most  of  them  are  connected  with
commercial gains for genetic engineering companies. A  popular  claim,  that
farmers will benefit, is simply not true. It is just  the  same  thing  with
consumers. No one is going to feed the poorest  with  GE  products  for  the
famine in many underdeveloped countries is simply the  matter  of  inability
to buy food, not lack of it. So today, at the present stage of  development,
we hardly need GE expanding on food products, needless to say  about  animal
and human cloning. Incidentally, some daydreaming proponents  of  GE  really
believe that mankind will not be able to survive without  it.  According  to
them, we will certainly have to genetically upgrade  ourselves  in  response
to governmental activities. The humans will be  able  to  hibernate    just
like some animals  to cover long distances without  aging,  and,  probably,
will become immortal
Still, what about the present need of GE? Where can GE particularly be  used
now without a threat to the humans and the environment?
So, scientists say that genetic engineering can make it possible  to  battle
disease (cancer, in particular), disfigurement, and other  maladies  through
a series of medical breakthroughs that  will  be  beneficial  to  the  human
race. Moreover,  cloning  will  be  able  to  end  the  extinction  of  many
endangered species. The main  question  is  whether  we  can  trust  genetic
engineering. The fact is that  even  genetically  changed  corn  is  already
killing species.
The recent research showed that pollen from genetically engineered corn
plants is toxic to monarch butterflies. Corn plants produce huge quantities
of pollen, which dusts the leaves of plants growing near corn fields. Close
to half the monarch caterpillars that fed on milkweed leaves dusted with Bt
corn pollen died. Surviving caterpillars were about half the size of
caterpillars that fed on leaves dusted with pollen from non-engineered
corn. Something is wrong with the engineered products  they are different,
so we cannot be sure about the effect they will bring about.
So, is the technology trustworthy? I suppose not.


Conclusion

So, do we need it? There are far too many disadvantages of GE and far too
many unpredictable things may happen. The humans are amateurs in this area,
in fact, they are just like a monkey taught to press PC buttons. We have
almost no experience, the technology has not yet evolved enough. I believe,
we should wait, otherwise we may give birth to a trouble, which would be
impossible to resolve.

References



1. David Heaf Pros and Cons of Genetic Engineering, 2000, ifgene;
2. Ricarda   Steinbrecher,   'From Green to Gene Revolution',  The
   Ecologist,

   Vol 26 No 6;
3. Genetic Engineering Kills Monarch Butterflies, Nature Magazine, May
   19,1999;
4. Who's Afraid of Genetic Engineering? The New York Times August 26,
   1998;
5. Sara Chamberlain Techno-foods, August 19, 1999, The New
   Internationalist;
6. W French Anderson, 'Gene Therapy' in Scientific American, September
   1995;
7. Nature Biotechnology Vol 14 May 1996;
8. Andrew Kimbrell 'Breaking the Law of Life' in Resurgence May/June 1997
   Issue 182;
9. Jim Hightower Whats for dinner?, May 29, 2000.

Contents

Introduction     1

What is genetic engineering? 1

  Techniques     1

The history of GE      2

  Selective breeding and genetic engineering  3

What are the dangers?  3

  Fundamental Weaknesses of the Concept 3

  Health Hazards 4

  Potential Environmental Harms   6

Any pros?   8

Conclusion  9

References  10