If the decoding of the human genome brings a new era of medicine, it will also need a new ethical and moral framework.

But many people believe the development of a code of conduct within which to exploit this potent new technology is lagging behind the accelerating scientific achievements.

One scenario centres on pregnancy. What if genetic testing of a foetus in the womb shows the child will die in its teens?

Professor Sheila McLean, Professor of Law and Ethics in Medicine at the University of Glasgow, says: "People who choose to continue with a pregnancy knowing that their unborn child is 'abnormal', may well be seen as irresponsible."

This could lead to unwelcome pressure, believes Dr Donald Bruce, of the Church of Scotland's Society, Religion and Technology Project: "There could be pressure for abortion, even potentially for economic reasons as well as welfare reasons."

Ethical worries

However, people whose families have suffered as a result of inherited disorders have a different perspective.

John Gillott, is policy officer for the Genetic Interest Group, a UK national alliance of over 120 charities supporting people affected by genetic disorders. He says: "A lot of the ethical worries are over anxious. I don't think that there is that cultural pressure relating to abortion in the UK.

"There are benefits of testing. It can set people's minds at rest and even if the result is positive for an abnormal gene, it's the gene, not the test, which has passed sentence."

However, Professor McLean for one, thinks that trusting people to act ethically may not be enough: "It is too optimistic about the human condition to imagine this pressure would not happen.

"We may be at the top of a slippery slope. We might initially eliminate all embryos and foetuses with cystic fibrosis. But the next step could be for late onset diseases like Huntingdon's, which people don't get until they are 40."

Social policy

Another concern is the future possibility of discrimination against people on the basis of their genetic inheritance. Could those deemed to be less intelligent be ruled out of certain jobs, for example?

Professor Robert Plomin, at the Institute of Psychiatry, Kings College, London, has conducted much-debated research which suggests a genetic basis for intelligence.

But he is not overly worried: "It doesn't necessarily follow that we give all of society's goodies to the kids who have those particular forms of the genes.

"In fact, you could take just the opposite perspective and say that, 'Based on my values, I think we should worry about the kids at the lower end of the distribution who are falling increasingly behind'.

"The more we talk about these things, the less frightening they become," he says.

Doctors and patients

The unique insight the genome provides of human illness raises further dilemmas, relating to the doctor-patient relationship.

For example, those relationships are currently one to one and confidential. But, in the future, what if a family member gets a positive test for an inherited disease?

Do you tell his sister, who is thinking of getting pregnant? What effect will that have on her marriage and the family group as a whole?

And lengthy counselling is acknowledged as being crucial to the healthy use of genetic testing, but if there are thousands of different tests, will the health services be able to cope with demand.

By BBC News Online's Dr Damian Carrington