A woman is to give birth this week to the first baby in Britain which has been selected to be free of a gene which greatly increases the risk of breast cancer, experts said.
The 27-year-old woman, who wants to remain anonymous, decided to take the step because several of her husband's close female relatives suffered from breast cancer.
But one campaign group warned that such selection takes science "further along the line which ultimately ends in designer babies".
Screened for BRCA 1 gene
The baby grew from an embryo screened to make sure it did not contain the faulty BRCA 1 gene, which would have given it a 50% to 80% percent change of developing breast cancer.
The mother said in June: "We felt that, if there was a possibility of eliminating this for our children, then that was a route we had to go down."
The procedure was carried out using a technique known as pre-implantation genetic diagnosis which has already been used here to screen embryos for disorders like cystic fibrosis. It was given the green light in Britain in 2006.
The procedure is still relatively rare but has been used to screen embryos for breast cancer in the United States and Belgium.
Help people with cancer genes
Paul Serhal, who led the team which carried out the procedure, said last week that scientists had entered "a new era of being able to help people who have cancer genes."
Josephine Quintavalle, of campaign group Comment on Reproductive Ethics, raised concern about discarded embryos, telling the BBC: "What next? It is going further along the line which ultimately ends in designer babies." – (Sapa-AFP)