The safety of embryo-testing techniques used to screen for genetic diseases and to create so-called designer babies needs more careful scrutiny, experts said yesterday.
Peter Braude, professor of obstetrics and gynaecology at King's College London, said the health of children subjected as embryos to preimplantation genetic diagnosis (PGD) should be tracked for five years.
Prof Braude said the risk posed by the screening technology, carried out on fertilised eggs produced during IVF, was low but needed to be checked.
He said: "I don't expect there to be abnormalities found, but there might be and I think we need to know whether this does cause any problems later. We do actually require some data to confirm that. There's lots of stuff when babies are examined at birth and they haven't found any problems but there's been nothing about following up those babies."
He called for a European register of babies born following PGD to monitor their health to early childhood. "We've got to make an effort to make sure."
PGD has been used routinely in the UK since 1990 to help couples who carry an inheritable disease to avoid passing it to their children. It identifies embryos with genetic defects and ensures healthy ones are implanted in the womb. Doctors remove one or two cells when an embryo is three days old and a ball of just eight cells.
Some experts suggest this could interfere with an embryo's later development, though Prof Braude said that freezing and thawing embryos - which reduces their number of viable cells - does not seem to cause health problems.
Several hundred babies have been born following PGD in the UK, most after screening for disorders such as cystic fibrosis and muscular dystrophy. More recently the technology has been used to check for diseases that will not strike the sufferer until adulthood, and also to create "saviour siblings" with the correct tissue match for a sibling who needs a transplant.
Alan Thornhill, scientific director of the London Fertility Centre, said new technology to amplify the DNA from the removed cells would soon allow doctors to test embryos for hundreds more genetic syndromes. Fertility clinics in Belgium already offer PGD tests for mutations in the BRCA1 and BRCA2 genes which make a woman up to 80% more likely to develop breast cancer.
There are moves to introduce the test in the UK, but it would first need approval from the Human Fertilisation and Embryology Authority.
Dr Thornhill said: "We can talk about is it right to do this or right to do that but it's already happening in the US and one or two other places in the world ... if people don't do it in this country then they're very likely to travel abroad to do it."
The technique could also allow non-fatal inherited disorders to be screened for, but Prof Braude said it would be too complicated to create "designer babies" selected for traits such as intelligence. "Most of them are designed only to live rather than die," he said.
