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What is Stem Cell Research and why is it Controversial ?
Definition of stem cells
Stem cells are generic cells, common to all multi cellular
organisms, which can replicate themselves indefinitely through
cell division. Moreover, a stem cell can produce specialized
cells for different tissues in the body like the heart muscle,
brain tissue and liver tissue. Scientists and researchers can
use stem cells in a wide variety of medical therapies.
In August 2001, President George Bush has legalized limited
federal funding for the stem cell research. Though stem cell
research has a great possibility to combat a wide variety of
serious ailments, it is also highly controversial. We will
discuss about that in the later half of the article.
What are the different kinds of stem
cells ?
There are two types of stem cells:
• The Embryonic stem cells
• The Adult stem cells
What are embryonic stem cells ?
Embryonic stem cell lines or ES cell lines are cultures that are
obtained from either aborted fetuses or fertilized eggs that are
left over from in vitro fertilization or IVF. These cells have
the ability to replicate each of the 200 different types of
cells that are found in an adult body when it gets the right
kind of stimulation for a particular cell type. They are
however, not responsible for the generation of any
extra-embryonic membranes or the placenta.
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As the embryonic stem cells have the
unique ability to expand indefinitely along with pluripotency,
they act as a great resource for regenerative medicines and
tissue replacements in case of accidents or other diseases. This
is why many countries are still not willing to allow scientists
to work on embryonic stem research or even produce any new
embryonic cell lines.
What are adult stem cells ?
Though termed as ‘adult’, these stem cells are found in both
adults and children. These are the uniform or undifferentiated
cells that are present all over the body; they divide to refill
the already dead or dying cells and also rejuvenate the damaged
tissues. Adult stem cells are also known as ‘somatic stem
cells’. Adult stem cell research has primarily concentrated on
elucidating their ability to divide or self renew indefinitely
and their differential potential. Quite a few adult stem cells
are classified as progenitor cells because of their restricted
capacity for cellular differentiation. |
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Adult stem cell research is not as
controversial as the embryonic stem research primarily because
generation or production of adult stem cells does not involve
killing or destructing of a foetus. In fact the government of
the United States of America has funded adult stem cell research
to encourage their development. Adult stem cell cultures can be
obtained from any tissue sample collected from an adult body.
Till date this has been studied in rats, mice and humans.
What are the various treatments that
are done with the stem cells ?
Scientists believe that stem cell research can bring remarkable
changes in the treatment of human disease. Today adult stem cell
therapies are used in treatments like leukemia for the
transplantation of the bone marrow. It is also considered that
the stem cells can treat other complex diseases like cancer,
Parkinson’s disease, injuries in the spinal cord, heart
diseases, arthritis, stroke and various muscle damages. However,
a lot need to be done before involving it in any such therapies.
What is the controversy relating to
the stem cell research ?
Embryonic stem cell research is highly controversial. This is
because, critics believe that the fertilized egg used is
primarily a human being that has the right to be protected. The
supporters or researchers on the other hand argue that the
ferttilized eggs used have the consent from each couple involved
and would anyway be discarded. So, there is no scope for those
eggs to mature into a human being. Nevertheless, this is a
highly debatable topic and controversies relating to it is
likely to continue for some more time.
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US
Government’s decision to finance Embryonic stem cell research
According to a report given by reuters, in 1999, the US
Government has taken the decision to finance all the research
using the master cells obtained from the culled human embryos.
However, the government funded scientists or researchers must
not grow the cells themselves. This decision from the government
has come despite severe oppositions from various religious and
ethics groups.
Though this is ‘an ethically sensitive territory’, scientists
strongly believe that embryonic stem cell research can lead to a
number of life saving therapies for infant diabetes, Alzheimer’s
disease and many other birth defects. The reason of this
controversy can be attributedto the fact that the ‘master cells’
collected are found only in early-stage human embryos. Few
anti-abortion groups find this research morally unacceptable as
they are collected from those embryos that have not been able to
live full term. This research has largely been restricted as the
federal laws prevent using the taxpayer’s money for conducting
studies using human embryos. |
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However, a group of scientists
performed these studies from aborted and unused foetuses from
the infertility treatments and was successful in replicating
them and using for research. These stem cells are lab grown and
hence do not constitute of embryos thus allowing the federal
agency to legally fund the experiments.
What are the International policies
relating to embryonic stem cell research ?
Embryonic stem cell research has drawn mixed reactions from
various countries of the world. Amongst the European countries,
Sweden, Finland, Britain, Denmark, Greece, Belgium and
Netherlands has permitted the research whereas Germany, Italy,
Austria, Ireland and Portugal consider it as illegal. In the
United States of America, the opinion is divided with a few
states imposing a ban while others granting financial support to
encourage it. Countries of East Asia including China, Japan,
Korea and Taiwan support this research while India still does
not have any policies but is in the process of formulating them.
Except Israel and Iran, all the other Middle east countries have
supportive policies towards embryonic stem cell research;
Australia is somewhat supportive whereas New Zealand, Africa
(with the exception of South Africa) and the major part of South
America (with the exception of Brazil) are compltely against it.
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Article Contributed By: Sukanya
Banerjee
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