Stem Cell Research

My Lords, I, too, thank the noble Lord, Lord Patel, for initiating this debate on a very important topic. Much of the debate so far has concentrated on the question of using animal ova to reprogramme human cell nuclei for research purposes. I make no apologies for returning to that subject. It is a very difficult topic for us to think about, because the revolutionary discoveries in biology over the past 50 years which underlie the possibility of stem cell therapies constitute some of the rare occasions when scientific advance must lead us to being more cautious about some traditional ethical arguments. The particular argument that I have in mind advances the claim that the unique moral status ofthe human embryo, from the earliest stage of its development as a fertilised ovum, derives from its unique potential—if many things occur in the right order—to become, in turn, an implanted embryo, a foetus, an infant and a person. However, once we appreciate the reality that cell nuclei can be reprogrammed—that is, that they can become less specialised and then be specialised in different directions—we can no longer be sure that this wide-open potential for developing into cells of all types will uniquely be found in the fertilised human ovum. So we have to rethink the traditional view that located the unique moral status of the humanbeing in a view about a unique biological route tohuman life. The dignity and moral standing of the human foetus and the human being cannot be read back or grounded in a claim that certain cell types—the fertilised ovum—have that status already and others do not, for we find that many cells have that potential if things happen in the right order. The skin cells that I would destroy by scratching the skin on my hand could have been reprogrammed by insertion of a nucleus into a human egg, which would have created cells with the potential for a full range of development into different cell types, yielding, in effect, human embryonic stem cells. We would risk absurdity if we tied human dignity to a story about a unique route of development. We now also know that the nucleus of a cell from one species can sometimes be reprogrammed so that it loses its specialised characteristics by placing it in the egg cell of another species, and may in turn yield human embryonic stem cells by that route, although we know that there are still many scientific questions to be answered because of the presence of mitochondrial DNA from the other species when that route is used. Why should we sanction the exploration of this potential? Why should we sanction research ofthis type? We should do so because we still need fundamental research on cell reprogramming—on the dedifferentiation and redifferentiation of cells, which will be the basis of any stem cell therapies. That should not depend on the use either of human embryonic stem cells derived from donated human embryos, or on the regular use of human ova—human eggs—donated by generous women. The Human Fertilisation and Embryology Act 1990—I am all too aware that I am standing next to my former teacher and noble friend Lady Warnock,whose report led to that legislation—has an interesting default structure, which is retained in the 2001 regulations. The Act and the regulations permit the licensing of research that uses human embryos only for limited and specific serious purposes, and then only if there is no other way in which that research can be done. It is the double default structure. If it were reliably possible to derive human stem cell lines by reprogramming cell nuclei using donated human eggs, that would be a reason for the Human Fertilisation and Embryology Authority to give licences for research using human eggs, rather than human embryos. However, human eggs are not readily available. Egg donation is a non-trivial procedure for the women who generously do it. Some, of course, do it as ancillary to their own fertility treatment, but that too is generous. This gives us strong reason not merely to permit but to require the use of animal egg cells for fundamental research on the potentiality of reprogramming human cells. Such cell constructs are being variously spoken of as hybrid embryos and cybrid embryos. The terminology is unsettled and unsettling, as is invariably the case in a period of fundamental revision of understanding. ““Hybrid embryo”” is particularly unfortunate, as it falsely suggests an intention to allow a hybrid being to develop, which our current legislation rightly forbids. However the terminology settles down, we should encourage the scientific investigation of ways inwhich stem cell lines with therapeutic potential canbe developed without either unnecessary research using human embryos or unnecessary research using human eggs.