The Irish Supreme Court recently judged that frozen human embryos are not among the "unborn" referred to in the Constitution, which binds the State to protect and defend the right to life of the unborn. The judges also called on the Oireachtas to introduce legislation to regulate assisted human reproduction and the Minister for Health, Mary Harney, has promised to introduce a Bill later this year, writes WILLIAM REVILLE
Advocates of human embryonic stem-cell research (HESCR) hope that these developments will soon give the green light to start up such research in this country. I am opposed to HESCR, primarily on ethical grounds and secondarily on practical grounds.
Biology shows that human life begins at conception when sperm and egg unite to form an embryo, thereby initiating a continuum of development that ends only in death. Science does not deal in ethics and cannot place a moral value on human life at any stage along the continuum. Many scientists believe, myself included, that human life has full moral value from the moment of conception, or at least sufficient moral value that it should not be deliberately destroyed. Many other scientists, probably a majority, believe that full moral value is only reached later along the continuum – at implantation in the womb or later. As the human embryo must be killed to obtain embryonic stem cells, I am opposed to HESCR.
Dr James Thomson, who discovered how to isolate human embryonic stem cells in 1998, has said: “If human embryonic stem-cell research does not make you at least a little bit uncomfortable, then you have not thought about it enough.”
This "yuk factor" associated with killing embryos affects most people and I believe that we should not override this deep-seated intuition. In his book, The Future of Human Nature, German philosopher Jurgen Habermas says: "There is a long-established, widely shared, deep moral intuition that human embryos are not just cells like any other cells, as some argue, and we breach that moral intuition at our peril." The deliberate killing of human embryos harms the respect for human life that we intuitively form around our coming into existence and may encourage a more general erosion of respect for life.
But people point to “surplus” human embryos left over from IVF procedures and ask why not use them for useful HESCR as they are destined to die anyway? Well, we are all destined to die, but this gives nobody the right to kill us prematurely and use our bodies for research. Also, “surplus” IVF embryos never asked to be created – they are an unfortunate by-product of IVF procedures. IVF techniques should be developed that do not generate “surplus” embryos and the embryos that already exist should be either adopted or allowed to die with dignity.
HESCR is primarily justified on the basis that it will cure many human diseases and therefore the benefit of the research greatly outweighs the harm done to embryos – the utilitarian ethic often expressed as “the end justifies the means”. Many scientists who carry out HESCR are intuitively repulsed by the idea of deliberately killing human embryos but override this feeling with the aid of the utilitarian ethic. On the other hand, principles-based ethics prioritises respect for human life and concludes that the hoped-for benefits must be sought in other ways that are ethical. Which brings me to the practical reason I oppose HESCR: we have very good alternative and ethical stem-cell approaches to curing disease – adult stem-cell research and induced pluripotent stem-cell research (IPSCR).
Adult stem cells can be prepared from umbilical-cord blood and from adult tissues. By and large, no ethical problems attend adult stem-cell research, which is forging ahead worldwide. Adult stem cells are much easier to control than embryonic stem cells and such research has produced more than 200 medical treatments. In contrast, no treatments are yet available from HESCR and it would be premature to expect any within 10 years.
Induced pluripotent stem cells, made by reprogramming ordinary adult body cells, eg skin cells, so that they change into stem cells, are the latest development in stem-cell research. Most indications are that such induced stem cells have as much potential in medicine as embryonic stem cells. By and large, IPSCR can be carried out without ethical problems.
Annual surveys of Irish public opinion carried out by Millward Brown IMS since 2005 show that the great majority of people want protection for embryonic humans enshrined in law. In the latest poll, 71 per cent of those who declared an opinion expressed a desire for legal protection for the embryo and 29 per cent saw no need for such protection ( Irish Times, May 15th, 2009).
William Reville is University College Cork's associate professor of biochemistry and its public awareness of science officer – http://understandingscience.ucc.ie