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As stem cells are the most
recent consequence of ever-accelerating biological progress, it
is not surprising that they are triggering most of the current heated
debates in the life sciences sector - debates which must steer a
course between two dangers. On the one hand, there is the risk of
taking hasty decisions (in particular under pressure from international
competition), and on the other of passing up the opportunity for
therapeutic progress able to relieve suffering and save lives.
The embryo dilemma
Embryonic stem cells pose
the most acute of problems. They can only be obtained from embryos
aged approximately one week, at the blastula stage. Yet research
on embryos is highly controversial, irrespective of the stage of
its development. A report by British stem cell experts summed it
up as follows: 'A significant body of opinion believes that, as
a moral principle, the use of no matter what embryo for research
purposes is neither ethical nor acceptable for the reason that an
embryo should be recognised as having a full human status immediately
it is conceived. At the other end of the spectrum, others claim
that the embryo neither requires nor merits special status. Others
accept the special status of the embryo as a potential human being,
but maintain that the respect due to the embryo increases as it
develops, and that in the early stages this respect must be set
against the potential benefits of research.'(1)
While some countries finance research on embryos,(2)
others refuse to do so, and some actually ban it outright (not counting
those with no legislation in this field). In cases where such research
is allowed, there is the question of where the embryos come from.
Researchers who have developed existing stem cell lines (the exact
number is not known, but it undoubtedly runs into dozens) have used
surplus embryos. These were created then conserved by freezing with
a view to in vitro fertilisation, but then ceased to be part
of a parental project, either because the couple had separated or
the (IVF) was successful. They were therefore destined to be destroyed.
It is not known how many embryos of this kind are available, and
if a major research activity were to develop, there are some who
inevitably envisage creating in vitro embryos specifically
for scientific purposes. Once again, such a decision would have
ethical implications as it would be seen as one more step in the
direction of embryo reification. Although it may solve the problem
of embryo supply, it would create another problem of ovary supply.
A number of problems are also raised by the use of tissues from
aborted foetuses as many individuals, and European countries, oppose
abortion.
Fear of cloning
Another controversial subject is the transfer
of the somatic nucleus, sometimes known as 'therapeutic cloning'.
This involves transferring the nucleus of a normal cell to a previously
enucleated egg, with the aim of creating an embryo carrying a patient's
genes in order to extract stem cells compatible with his immune
system. In this case, too, there are accusations of embryo reification
and, what is more, of opening the door to reproductive cloning or,
in other words, the universally condemned practice of creating an
embryo carrying the genes of a single individual and then bringing
it to its full development.
Finally, present research is taking place
within a varied and changing legal framework. Questions are being
raised about ownership of cell lines and the tissues they can create
and eventually transplant (these cell banks will soon be a reality),
and on the patentability of the products and techniques which originate
during such research.
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