SCIENCE AT THE SHINE DOME canberra 4 - 6 may 2005

Symposium: Recent advances in stem cell science and therapies

Friday, 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.