Cloning is the process of creating an identical copy
of something.
Cloning a cell means to derive a population of cells
from a single cell. A
clone shares all the genetic characteristics of the original cell. However, we must differentiate between the scientific
definition and the definition of the general public
In fact, when we talk about cloning in the general public,
they immediately think about the technique is to create an individual with the
help of stem cells. While scientists speak of clones from the moment two cells
have the same genetic heritage. They distinguish between clone "in
vivo" when it comes to individuals and clones "ex vivo" when it
is simply cells.
Thus according to the scientific definition, contrary to
what we may think, cloning is something that has existed for a long time and is
widely practiced in nature. Indeed, for example in humans, the cells renew
themselves by multiplying at the same: it’s the mitosis.
After fertilization, we can also observe the phenomenon of
cloning: Initially there is a cell that makes mitoses then each cell
specializes in a spot to give cells in the heart, brain, eyes… Cloning is a completely natural phenomenon.
As for manipulation by human cloning, contrary to popular
belief, it is also long overdue. Indeed, first in plants, cloning results in
the plant cuttings: in taking a rod and the replanting creates a new plant,
which have exactly the same genetic inheritance, it is a clone.
Dolly, a female sheep was the first mammal
to be cloned from an adult somatic cell,
using the process of nuclear transfer.
The technique of cloning provides a solution for the
survival of endangered species. So in January 2001, on a farm in Iowa was born
wild ox. Noah is the first clone obtained from the cells of an animal in danger
of extinction. It will still required 700 eggs from cow to arrive at the
result.
But is striving to repopulate the species almost extinct
from a very low genetic diversity? Will extend the feat in recreating species
disappeared completely as the Tasmanian tiger that some would like to see revived?
Cloning is another solution to treat certain diseases such
as Parkinson's disease and Alzheimer's. They may treat spinal cord sections,
something that has been practiced successfully in rats. And the risks of
rejection are virtually non-existent because the stem cells come from the
individual treaty. So thanks to cloned cells, we can cure diseases still very
poorly controlled nowadays…
Cloning is also as a solution to the sterility of a couple.
Currently, the couple use of donated gametes: The child who is born, has a
genetic heritage sometimes totally different if both spouses are sterile. Now,
thanks to cloning, it would be enough to charge cell nuclear any of the couple
and the child that would result corresponds to a combination genetic quite random
and unique.
There are many problems caused by cloning. Firstly, there
are difficulties associated with the birth and survival of clones. We found an
aging faster than normal at Dolly.
Moreover, although theoretically the cloning appears to be a simple
technique is well known, obtaining a clone is difficult. For example, Dolly was
born after 300 attempts.
Transplantation
of organs and tissue from animals to humans is dangerous. Studies show
that retroviruses are believed to be at transplatation.
In addition, although cloning is establishing itself as the
solution to species extinction, it can also lead to the disappearance of a
species. Indeed, the survival of a species through the centuries is based on
the diversity of their genetic heritage: the rich heritage, allows a person to
be better armed to deal with viruses and epidemics.
Finally, it seems that all the advantages offered by cloning
seem to be totally utopian: all these notions are still largely inaccessible
today. However, although all applications are still within the realm of dreams,
those ideas are necessary for the progress of science and to guide the
research. Unfortunately, at present, there seems to be more disadvantages than
advantages to practice cloning.
In addition to these technical problems, the most important
problems are the ethical issues such as cloning a deceased child, the concept
of eternal life and of course the fear Drift…
Finally, many moral questions are raised today about the
cloning. What are the limits of cloning? And what impact can lead to the human
race? All these questions, of course, the slow development of technology and
research, but one of the essential elements of these discussions is to avoid
any blunders that could have irreversible consequences on humans. That is why
all this is necessary. Indeed, they enable scientists to be aware of the
dangers and risks they can to avoid slippage. In addition, they can also lead
to better research as required… These ethical issues no longer act as an
indispensable guide rather than a brake.
Thank for your help