The 'yuk factor' is not a good enough reason to deplore James Whitaker's birth

There is no slippery slope here, but a bumpy ascent, which will be difficult to navigate and fraught with disappointment

Five-day-old James Whitaker is a baby with a job to do. His conception and development have been conducted with a special purpose in mind. If James's tissue matches that of his brother Charlie, and if he does not have the same genetic disorder that his brother has, then blood and stem cells taken from his umbilical cord and placenta will be used in an attempt to cure Charlie of diamond blackfan anaemia.

The chances of a tissue match are high at 98 per cent, while the chances of James also having diamond blackfan anaemia are low at 2 to 3 per cent. There are no available odds on whether or not the stem cell transplant will in itself be a success, because too few have been carried out for statistics to be extrapolated. But the first time this treatment was tried, for a toddler from Colorado, Molly Nash, who suffered from Fanconi's anaemia, it was successful. Surely no one could wish for anything less than the same success for Charlie Whitaker.

James Whitaker has been billed as Britain's first "designer baby". But this is not true. This baby has not been "designed". He has achieved life, while potential siblings were destroyed, because his beginnings fulfilled certain criteria.

But his flesh and blood, preferred because it suited another purpose, was not actually engineered in any way for that purpose. His life was chosen, while other lives were rejected. In IVF this happens often. James was chosen, using scientific techniques, not designed by them.

Yet an uncomfortable line has still been crossed. The Human Fertilisation and Embryology Authority is in no doubt of this. The Whitakers sought their treatment in a Chicago clinic, because the practice of matching embryonic tissues in order to create donor material for siblings is banned in this country.

Even this line is not as clear as it might be. While the Whitakers were turned down by the HFEA, the Hashmi family, who wish to have another baby in order to gain a bone marrow transplant and save their son Zain, who suffers from beta-thalassaemia, have been given the go-ahead.

The difference between the two cases is a subtle one. In this country, medical screening of embryos can only be done when there is a potential gain for the possible child-to-be. The Hashmi family's treatment involves screening embryos for Zain's disease, and rejecting those which carry it. Since there is no such test for Charlie's disease, there was no medical benefit in the procedure for James, so the Whitakers went to the US instead.

If this distinction seems technical enough to be almost arbitrary, then that is because in vital respects, it is. Practically speaking, for example, the Whitaker scenario makes more sense rather than less. The benighted Hashmi family may have the HFEA's seal of approval. But their chances of gaining the result they crave are much lower than the Whitakers.

Shahana Hashmi has already undergone one termination, and two unsuccessful attempts in the US to create a suitably life-saving sibling for Zain. Her chances of producing a donor are put at 2 to 3 per cent. Even if she eventually gives birth to a suitable child, bone marrow transplants fail in 20 per cent of cases and in 10 per cent, result in death. Often in science - which we see as all-powerful - the ethical discussions leap far ahead of what is actually possible. Zain Hashmi is reported to have said to his father, after permission to proceed had been granted: "We've done it Dad. I can get better now." Sadly, that is far from necessarily the case.

This odd ethical guideline, citing medical benefit to the embryo, has already thrown up some other disquieting anomalies in Britain. For example, sex selection screening in this country is banned for the purpose of family balancing. Yet a couple of clinics in this country are now licensed to offer sex selection for medical reasons. So families with autistic children can have sex selection screening and destroy male embryos because they are four times more likely to have autism than girls. There is no genetic test for autism itself, for no gene for it has been found, even though the condition is inheritable. The male embryos are simply rejected on the grounds that autism is far more prevalent among boys. For a healthy male embryo to be destroyed on such grounds does not speak to me of a "medical benefit".

At the same time, it does not do to be too squeamish when considering these matters. After all, the abortion of perfectly healthy babies simply because the mother prefers not to have them is widely considered acceptable in this country, and it could be argued that the destruction of single cells is preferable to this.

Of course, for many of those against abortion - the pro-lifers - all procedures which involve the destruction of human life at any stage are unwelcome. That is why Josephine Quintavalle, of Comment on Reproductive Ethics, twice challenged the HFEA's decision to allow the Hashmis to seek to give birth to a donor for their son.

For many others though, the distaste for modern reproductive science is more nebulous, with the cry each time a boundary is crossed being of "slippery slopes" towards "designer babies". The reality is considerably more quotidian. There is no slippery slope here, but instead a bumpy and hazardous ascent, which will be difficult to navigate, and fraught with disappointment. Even IVF, among the most straightforward of reproductive technologies, has become notorious for its 24 per cent success rate. The idea that reproductive technology is suddenly going to make such a leap that babies can be designed, and engineered to possess desirable traits, is most unlikely.

No single gene has been discovered for intelligence or artistic ability or charisma or attractiveness, and even if it were, there would be no guarantee that any attempt to introduce such a gene would not have a detrimental rather than advantageous effect on the recipient's general ability to function. In the murk that surrounds reproductive issues, we can be sure of one thing. James Whitaker's birth does not herald the start of the designer baby era.

Yet even when the "slippery slope" unease is removed, there is still a "yuk factor" involved in the idea of this birth. Robert Winston, the nation's favourite fertility guru, recently spoke of his unease at a child becoming "a commodity, a human born not for its own sake but because other people have a purpose for it".

That, I think, is the essence of the feeling of unease that niggles at people. In answer to this, I would suggest that such sentiments have more to do with our society's unrealistic idealisation of parenthood. Parenthood is never selfless, however much we wish to aggrandise ourselves by believing that it is. Most parents have children because they want them for their own fulfilment, not because they want to make a miraculous contribution to the sum of humanity.

Many have them just because they failed to use the contraception they should have, or because pregnancy and childbirth is a time of attention and interest in an otherwise joyless life. Occasionally, people have children for extremely selfish reasons - in order to impose emotional blackmail on a partner, to ensure a supply of family labour, or care in old age, or for "continuation of their line".

Plenty of people, without the intervention of science, have already had more children in the hope that they would provide some kind of transplant match. For people this desperate, and this loving, science has merely introduced a little more hope.

d.orr@independent.co.uk