I hate to be a spoilsport, but don't get so excited over the genome project

'This advance is of enormous importance. But change our lives in the next 20 years? Nah'

Is it really bigger than antibiotics, as our Prime Minister claims, or is it more like nuclear power, a commercial blind alley? No one should doubt the technical and intellectual achievement of the mapping of the human genetic code, but the practical and commercial applications of great scientific advances often do not match the promise they initially show.

Is it really bigger than antibiotics, as our Prime Minister claims, or is it more like nuclear power, a commercial blind alley? No one should doubt the technical and intellectual achievement of the mapping of the human genetic code, but the practical and commercial applications of great scientific advances often do not match the promise they initially show.

Antibiotics have indeed utterly transformed the human condition, both at an individual level and a societal one. Many people reading this newspaper would not be alive now were it not for antibiotics; and the world's population and age structure would be totally different.

But the practical applications of nuclear power have been quite limited and the costs vastly higher than the scientists promised. In the Fifties, British schoolchildren were taught that we had a global lead in the peaceful use of nuclear energy: that Calder Hall was the first commercial nuclear power station in the world. As we grew up, we were told that power would be so cheap and clean it would not even be metered: we would just pay a small fee on the rates as we did for water and other public services.

There have been many other disappointments, from the helicopter (useful but limited) to human space travel (being abandoned). But there have also been surprises, where a technical advance that is initially unheralded does transform human life: the internet being the most recent example. Now, given this experience, apply a sensible non-scientific scepticism to this particular advance. What, in 20 to 40 years, will be said about the decoding of the human genetic chain? At the risk of being a spoilsport (and of being spectacularly wrong) here are some suggestions.

The history of applying technological breakthroughs suggests that the practical uses of the new knowledge will take at least 20 years to feed through. It has taken us 40 years to go from Crick and Watson to Frankenstein foods. As the economist Alfred Marshall pointed out 80 years ago in his book Principles of Economics, the full implications of any great scientific breakthrough are not evident in the generation in which it is made. The advances only become useful for practical purposes when a host of subsidiary inventions and discoveries are made after the original breakthrough. So expect very little of practical use in the next 20 years. There will be lots of noise: announcements of new discoveries and some new services. But there will not be much significant change in the lives of the vast majority of people, even if the breakthough is as big as Tony Blair and Bill Clinton suggest.

Whether things change radically in the period beyond 2020 will depend on two things: the further inventions and discoveries still to be made and whether what we, as human beings, really, really want can indeed be delivered at an acceptable cost.

On the former, all we can say is that while there will be a hunt to find applications - the commercial prizes seem so great - the really important subsidiary advances will probably not be made as a result of any of the efforts of established biotech companies. The advances are more likely to come from lone researchers in a university or even individuals in their garage. That has always happened in the past (think of the World Wide Web and the browser) and it would be surprising if the pattern were to change now.

As for the latter point, we know what we want and that is a start. We want to be healthier and we want to be happier. In theory any further knowledge of genetics should help us towards achieving the first. And some things will happen. It would be very disappointing were there no practical advances in healthcare as a result of this breakthrough.

But, as far as the general health of a population is concerned, we could achieve much more, in the short-term at least, by applying more thoroughly what we know already rather than hoping for a pay-off from a breakthrough. Were we in Britain to apply global best practice in health care and find a way of persuading people to follow healthier lifestyles, the change we could make over a generation would be enormous.

And happiness? Leaving aside the uncomfortable possibility that if people lived healthier lifestyles they might be less happy, not more, I find it hard to see this being as big as antibiotics. Seeing loved ones struck down bycapricious diseases that can now be cured was one of the agonies that our ancestors had to suffer. That source of misery is much less likely now, though we should be aware that, in some cases, antibiotics are becoming less effective.

We will know more, but for quite a while there may not be much we can achieve with that knowledge. We may find that the main use of the knowledge is to confirm theories and ideas that we were already pretty sure about. Happier? Not really; maybe less happy if we are having our fears confirmed rather than our hopes satisfied.

There is however one hope that is worth noting: that in understanding more about the extraordinary complexity of the human being, we will also come to understand how similar we are to the other creatures with whom we share the globe. I saw a statistic the other day. We share 92 per cent of our genes with the higher apes. We can all detect human characteristics in the behaviour of domestic animals, especially dogs. But we also need to acknowledge and respect the rights of our less agreeable neighbours: I'll happily swat a wasp, but we would all be diminished if there were no wasps left.

Hopefully the more we understand about ourselves the more we will understand about why we are here at all. So maybe the appropriate parallel is not with antibiotics or with nuclear power but rather with Charles Darwin. If you take a very long view of history, this moment in the development of humankind is an extraordinary one. There is an explosion of knowledge, of technology and of sheer human numbers. It is thrilling, but it is also profoundly dangerous. We have the capacity to do a lot of damage both to the planet and to ourselves; the more we understand about ourselves, maybe, the less chance there is that we will do that damage.

So yes, this advance is of enormous importance. But change our daily lives much in the next 20 years? Nah.