Cloning

Cloning is a technology and indeed a subject that has gripped the public imagination. The mere mention of the word 'cloning' sells books, films and even newspapers. Cloning also raises blood pressure and causes panic in equal measure and to an extent unprecedented in recent science.

More importantly perhaps, Dolly, or the technology by which she was created, raises many different sorts of important questions for us all. Some of these questions concern human rights and how we are to understand the idea of respect for these rights and for human dignity. Others direct our attention to the ways in which we attempt to pursue scientific research and bring that research to the point at which it is safe to offer therapies or products to the public. Other questions make us reflect upon the ways in which we attempt to regulate or control both science and indeed personal and public access to the fruits of science. Finally there are fundamental issues about the standards of evidence and argument that we do or should demand before we attempt to control or limit human freedom. All of these questions and issues are of the first importance and all of them come together and are engaged when we consider the ethical, legal and regulatory issues presented by human cloning.

Cloning refers to asexual reproduction, reproduction without 'fertilisation'. A cloned individual (clone from the Greek Klon , 'twig', 'slip') may result from two different processes: (1) Embryo splitting: this sometimes gives rise to monozygotic twins but can also result in identical triplets or even quadruplets. (2) Cell Nuclear Replacement (CNR) or Cell Nuclear Transfer (CNT). This was the procedure that produced Dolly. CNR involves two cells: a recipient, which is generally an egg (oocyte), and a donor cell. Early experiments mainly made use of embryonic cells, which were expected to behave similarly to the cells of a fertilised egg, in order to promote normal development after the nuclear replacement. In more recent experiments, the donor cells were taken from either fetal or adult tissues. The nucleus of the donor cell is introduced into the egg (either by cell fusion or by injection). With appropriate stimulation - electric pulses or exposure to chemicals - the egg is induced to develop. The embryo thus created may be implanted in a viable womb, and then develops in the normal way to term, although the failure rate has so far been high.

It is clear then that cloning did not start with the birth of Dolly nor yet did artificially produced clones start with the birth of Dolly. The first type of cloning was, as we have noted, the creation, through sexual reproduction, of so-called identical (monozygotic) twins. These sorts of clones have always been with us and , confining ourselves to humans for the moment, humankind has a vast, and on the whole successful, experience with them.

When identical twins occur in nature they result from the splitting of the early embryo in utero and the resulting twins have identical genomes. This process can be mimicked in the laboratory and in vitro embryos can be deliberately split creating matching siblings.

This process itself has a number of ethically puzzling if not problematic features. If you have a pre-implantation embryo in the early stages of development where all cells are what is called 'toti-potential' (that is where all cells could become any part of the resulting individual or indeed could develop into a whole new individual) and if you take this early cell mass and split it, let us say into four clumps of cells, each one of these four clumps constitutes a new embryo which is viable and could be implanted with the hope of successful development into adulthood. Each clump is the clone or identical 'twin' of any of the others and comes into being not through conception but because of the division of the early cell mass.

Moreover, these four clumps can be recombined into one embryo again. This creates a situation where, without the destruction of a single human cell, one human life, if that is what it is, can be split into four and can be recombined again into one. Did 'life' in such a case begin as an individual, become four individuals and then turn into a singleton again? We should note that whatever our answer to this question, all this occurred without the creation of extra matter and without the destruction of a single cell. Those who think that ensoulment takes place at conception have an interesting problem to account for the splitting of one soul into four, and for the destruction of three souls when the four embryos are recombined into one, and to account for (and resolve the ethics of) the destruction of three individuals, without a single human cell being removed or killed. These possibilities should, perhaps, give us pause in attributing a beginning of morally important life to a point like conception.