SCIENCE AT THE SHINE DOME 2005: ANNUAL SYMPOSIUM
Recent advances in stem cell science and therapies
6 May 2005
Session discussion
Chair: Professor John White, FAA
Speakers: Professor Julian Savulescu and Professor Bob Williamson, FAA
Question Bob, I can’t
see any way to accepting your argument that the nuclear transfer group of cells
doesn’t constitute an embryo. We have the very fact that Dolly was born, and
the many species afterwards in which that was done. Accepting the fact that it
has got a high attrition rate and it has got other problems, the fact that it
is capable of happening means that surely this is an embryo.
Bob Williamson – I respect
what you are saying, and I know the problem you are addressing. A proposal has
come from Norman Ford that one really has to look at the primitive streak as
the time when the embryo acquires the degree of individuality such as to
deserve respect, and Caroline Cameron and I have put forward a proposal in a
very recent article in the Journal of Medical Ethics that implantation
is the moment we should look at. Personally, I am not against according respect
to embryos. I think that is a fundamental human issue.
But there is no fertilisation. Although
I am not a Catholic, I agree that there is a certain wonderful simplicity in
taking that moment when the sperm hits the egg as the moment when a ‘new’
genetic biological and social entity starts. That being said, however, in
nuclear transfer there is no sperm, and soon there will be no egg. When there
is no sperm and no egg you will lose that moment in time. And because of losing
that moment in time I would suggest that either the primitive streak or the
moment of implantation should be the moment that one looks at in redefining
this.
Question (continued) You
used the word ‘embryo’ there a few times, but the fact doesn’t change: when Dolly
was born, the cat was born, the mice and the cows were born, they weren’t born
because there wasn’t an embryo. There was an embryo.
Julian Savulescu – I think
that this is an area where you have to be very clear about what the definitions
are. You just have to settle on a definition of ‘embryo’ and then decide
whether a cloned cell is an embryo.
If an embryo is a cell with the
capacity or the possibility of producing a live-born baby if implanted in a
uterus, it clearly is an embryo. But then the question is: what is the status
of that embryo? I think very often people don’t define clearly what they mean.
And then they don’t ask the further question: well, what is actually the moral
status of that entity? They often have the idea that an embryo is a
baby. It is not a baby, it is a cell with a certain kind of potential.
So I think we have a lot of work to
do in just getting the definitions right, before we make any progress with the
ethical debate.
Question I have done
a bit of mouse cloning in my time, and I want to take up that point and say
that I agree with what Bob is trying to raise in terms of trying to get the
discussion away from calling a cell an embryo. I agree it is not cloning and
making a new individual; I think that is a clear distinction.
But until we can discover the
factors that create reprogramming, and we isolate embryonic stem cells from a
blastocyst – because it is that structure – we can’t really call it a diploid
cell. If you could just put the nucleus into an egg and have it turn into an embryonic
stem cell equivalent, then I agree it would be a diploid cell. But when you
have to go through a differentiation event, in effect, forming a trophectoderm
inner cell mass, it has to be called an embryo, I think.
Question I think we
have got to be very careful that we don’t go back to the Middle Ages argument
about how many angels can stand on the head of a pin.
My thinking about embryos was
changed totally by a birthday card I received from my daughter. It contained a cartoon
of sperm swimming across the page, and one sperm saying to another, ‘Do you
believe in life after birth?’ I think that’s fantastic – except that I think it
should be ‘Do you believe in life after fertilisation?’ And that is why I am
wearing my sperm tie.
Let’s try and get the best out
of this. I am sure there is nobody in this room, after these fantastic talks
that we have had today, who would even contemplate human reproductive cloning.
It’s out. We have moved beyond that. We don’t want it. But stem cells must be
in, because we desperately need them. And I think that, as Bob and Julian have
said, it would be morally repugnant to pass legislation that inhibited any
research on stem cells.
Question I address
this to Bob. I think the previous question implied that there is no need for
any legal basis, but would you oppose a legal basis banning human reproductive
cloning?
Bob Williamson – I believe
that the community will be reassured and has a desire to place a definitive
legislative wall that defines a particular point where it does not wish science
and medicine to go. And I believe that point defined by the community is human
reproductive cloning.
I disagree with Julian about human
reproductive cloning, in that I think it is unethical. The reasons are
all fairly sophisticated, and having said that, I probably agree with him that
on a scale of 1 to 10 it is not amongst the worst things that happen in a
society where we need only read the papers to see what goes on around us that
is really unethical.
I also think that one of the
reasons why I am willing to go with the public view on human reproductive
cloning is that I can think of absolutely no medical reason which
justifies human reproductive cloning. And because I can’t think of any medical
reason for doing it, I don’t think that setting that as a limit really matters.
So the answer is yes, I would be
totally at ease to see the sort of thing I had in one of my PowerPoint slides
toward the end put forward as a firm piece of legislation.
I do think that research should be
regulated by regulations and by ethics committees and by public bodies, and
research should in general not be regulated in law. I will give you an example
from Victoria.
From 1997 until 2002, Victoria was the only jurisdiction in the world where Dolly-cloning of humans was
explicitly legal. And the reason it was explicitly legal was that in 1995 the
parliament passed a law saying that human cloning is illegal and, should you do
it, you will serve four years at Her Majesty’s pleasure in Pentridge. But this
is criminal law. In criminal law, what the parliament says is what it means.
And the line above said, ‘A human embryo is formed by the union of an egg and a
sperm going through syngamy.’ And since in Dolly-cloning there is no sperm, the
result was not, by law, an embryo. (That is, by the way, why the definition in
the Commonwealth law and the law today is so vague. It isn’t actually a
definition at all.)
So I think the criminal law is not
usually the best place to regulate a rapidly moving scientific area. Whatever
you want to achieve, I don’t think it is a good way to do the regulation.
Chair – I hope that you will
join me in thanking both Bob and Julian for bringing this important part of the
subject to you.
I would like to say for my part that
I am looking back now three years to when we discussed this before, and what I
see is a great number of developments. What we have seen today has been a great
evolution of what was there present a few years ago. And it is that evolution
of the science that I think we have been mostly sensitive to – certainly I have
been mostly sensitive to – during today. It is an extremely important matter.
Secondly, I also see that part of
that evolution and development has led to a whole lot more questions. I was
most struck by the comment this morning that there can be sub-populations of
embryonic stem cells. I was most struck by the comment by Bob on the subject
that there could actually be cytokines that are being delivered when stem cell
treatments are being offered from bone marrow and so on. Many things to
resolve.
And I think that for me – and I’m
sure that you would all agree – the basic plea is the question of how can this
proceed.
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