The cracking of the genetic code presents many opportunities for human betterment, even if they are somewhat further in the future than most popular commentators, inebriated with their own hype, allow. But it also presents two dangers.

The first is another dose of scientific reductionism. Ironically, given that he is a southern Baptist, this was somewhat poetically summarised in the words of Bill Clinton, who marked the announcement by proclaiming that we were "learning the language in which God created life". More prosaically, James Watson, the co-discoverer of DNA, said: "Now we know, in large part, that our fate is our genes." New Scientist's opinion was: "Monday 26 June will be remembered as the day when humankind learned, in a sense, what it is to be human."

In fact, humankind learned that only in the sense that a map shows a country but does not describe a national culture or a society. Many scientific and other discoveries have sought to explain our humanity. Many contain a truth but none the whole truth. The human genome project marks a great advance in our understanding of genetics, albeit something of enormous significance. But it does not explain the whole, or perhaps even the most significant part of our human essence. To reduce human beings to the sum of their parts - their minds, their economic motivations, their genes - is to make them less than they are. But also more than they are. We are creatures capable of great scientific, human and artistic achievement but also creatures who are flawed, who often fail, perhaps inevitably, to live up to our better selves and our possibilities.

We are also social beings and so it is ironic that at a time when social science's explanations of human behaviour are often treated with caution, if not downright disbelief, that our genetic selves should now be being seen as an explanation for what we are.

Such reductionism is related to the second potential danger that the new discovery presents. It regards human beings as infinitely perfectable - we are told that cancer, Alzheimer's disease and a host of other ailments that the flesh and mind are heir to may be things of the past. Some of this has a strong element of wishful thinking. Genetic engineering to remove the possibilities of disease is not like changing a fuse, as is being implied. For example, cystic fibrosis has been linked to more than 1,000 different mutations. It is also the case that many people who harbour the potential for genetic disease choose not to be tested. In the case of Huntingdon's chorea it is only a very small minority. This may seem strange but then this is another of those facts of human nature that not even the DNA map can explain.

But behind these predictions of wiping away all our tears, lies an implied belief in human perfectibility, the corralling of at least one of the four horsemen of the apocalypse - disease in its widest sense of not the physical but other kinds of human defect.

Genetic engineering raises the question of the place of suffering in our world. We are being assured, of course, that eugenics is now so discredited by its Nazi past and the horrors perpetrated in Sweden and the US in the 1920s and 1930s that no state will now countenance it. Perhaps not as an instrument of public policy. But cosmetic operations have been performed, at parents' request, on children with Down's syndrome to remove Down's features. Women with learning difficulties have been sterilised without their consent. Given this, is it difficult to envisage "benevolent" court or medical decisions, at the behest of parents and others, to attempt to correct, by genetic means, what nature has made?

Suffering is all around us, much of it not preventable by scientific or other means - loss, misfortune, death, increasing incapacity. To say that it is often unavoidable is not to be complacent or resigned. It is human to feel anger and to seek cure, alleviation or prevention. But we also have to take suffering and make what we can of it. Mary Craig, a mother of two sons with a severe learning difficulty, knew that it defeated some people and was the making of others. As she wrote in Blessings: "The real tragedy of suffering is the wasted opportunity."

Suffering can lay bare the essential self, which is not always the best self. It can strip us of all that is extraneous to our true nature. Pierre d'Harcourt, reflecting on his experience of Buchenwald, said that cleverness, creativity, learning all went down - "only real goodness survived".

The balance to be struck is in recognising the limits of human intervention, an acceptance of suffering and the desire to do all we can to overcome it. Those who hold that existence is finite may find this more difficult than those who take a transcendental view. But why we suffer and how we meet suffering is another thing not written in this newly opened book of life.

Terry Philpot is editor-in-chief of Community Care and is writing a book on monasticism.

© Guardian Newspapers Limited 2000

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