Fear and cloning

一月 30, 1998

Why fraternity cannot be cloned. Ayala Ochert discovers almost is not all

The Human Genetics Advisory Commission wants advice on human cloning. Yesterday, with the Human Fertilisation and Embryology Authority, it issued a consultation paper seeking views on the ethics of cloning. "It is we the public who should control science, and not the other way round," declared Sir Colin Campbell, chair of the HGAC.

The paper suggests that we distinguish between "reproductive cloning", the aim of which is to create whole human beings, and the use of "cloning technologies" for research and potential medical therapies that do not involve creating a whole person from another's cells. The suggestion is that cloning technologies be practised on human embryos up to 14 days' old that are left over from unsuccessful fertility treatment.

Although current legislation, administered by the HFEA, does not explicitly rule out reproductive cloning by nuclear transfer (the technique used to create cloned sheep Dolly, in which the nucleus of an adult cell is fused with an egg cell whose nucleus has been removed), the consultation paper makes clear that the authority will not allow this or any other form of reproductive cloning. But it keeps open the question of using cloning techniques, and it is views on this that the HGAC is most interested in.

Campbell stresses the importance of rationality when addressing human cloning: "We are trying to explain what is going on, the possible dangers and the possible benefits. You get all sorts of fantastic images; but let's talk about the issues, not the images. People think it's about Saddam Hussein and Adolf Hitler, but it's much more fundamental: how does your body work, how do cells grow, how does cancer spread, how do you age? If we can understand how they work, it might give us the capacity to intervene."

To scientists involved in basic research, Dolly represents more than a technical advance - her existence demonstrates the principle that the genes of an adult cell can be reprogrammed to return to an "embryonic" state. And they still have everything they need to form a whole organism, which has implications for theories of how cells and organisms develop.

Outside basic research, the paper points to two potentially significant, and possibly controversial, applications of cloning technologies.

The first is a suggested way of avoiding diseases passed from mother to child through the mitochondria, parts of the cell that sit outside the nucleus. A woman with a mitochondrial disease might ask to have the nucleus of one of her eggs transplanted into an unafflicted woman's egg. This hybrid egg could be fertilised using her partner's sperm via in vitro fertilisation. This procedure would not involve creating a cloned embryo, but it might be seen as a type of genetic engineering, and therefore be considered unacceptable.

The second potential medical use of cloning technology mentioned by the paper relates to in vitro stem cells. It is envisaged that these could be used to treat diseases such as Parkinson's, or to create new skin tissue for burns patients or muscle tissue for heart patients. The idea is to take the nucleus from a patient's cell and transfer it to an egg cell whose nucleus has been removed. At this point, a cloned embryo will have been created. That embryo would not develop into a person; it would be used to create stem cells. If injected into the brain of someone with Parkinson's disease, these stem cells might grow into healthy neural tissue and possibly reverse the disease. Stem cells are at such an early stage of development that they are in principle able to form any human tissue.

When the consultation finishes at the end of April and the results are presented to ministers, the question of whether to allow these potentially beneficial applications will be at the top of the agenda. The HFEA is clear that human reproductive cloning is banned, but it has taken this opportunity to pool opinions on cloning in its widest possible sense, even on currently illegal practices .

It asks, for example, if it is ever acceptable to clone humans, for example to "replace" a lost relative or to create a suitable organ or tissue donor, or whether humans must always be ends in themselves and never means to someone else's ends? And is it more unnatural to use a procedure such as nuclear transfer, which has no counterpart in nature, than a technique like IVF that mimics a natural process?

Copies of the consultation document from: The HGAC Secretariat, c/o Office of Science and Technology, Room G1, Albany House, 94-98 Petty France, London SW1H 9ST



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