A mum has conceived the first British baby guaranteed not to suffer from hereditary breast cancer.
The girl was at high risk of contracting the disease as her father carried the harmful BRCA-1 gene and three generations of his family had suffered from breast cancer.
Doctors at University College London Hospital were able to screen out the gene in the womb.
Any daughter born with the gene would have had a 50 to 85% chance of developing breast cancer and the 27-year-old British mother said she felt it was her duty to protect her future child from the illness.
She and her 28-year-old husband had to go through IVF treatment – even though they are both fertile – so that the embryos could be screened.
The couple produced 11 embryos, of which five were found to be free from the gene. Two of these were implanted in the woman’s womb and she is now 14 weeks pregnant.
By screening out embryos carrying the gene, the couple, will eliminate the hereditary disease from their lineage.
About 5% of the 44,000 cases of breast cancer diagnosed in Britain each year are estimated to be caused by the BRCA-1 and BRCA-2 genes, both of which can be detected in embryos.
Doctors say thousands of cases of breast cancer could be avoided by screening embryos using the technique called preimplantation diagnosis (PGD).
Many women who test positive for the gene have their breasts surgically removed to avoid the disease.
Only one other woman – an Israeli mother-to-be – is thought to have become pregnant after undergoing the embryo screening.
The British couple’s doctor, Paul Serhal, medical director of the Assisted Conception Unit at University College London hospital, said the breakthrough gives parents the option of avoiding passing a high risk of breast cancer on to their children.
He told the Sunday Times: “Women now have the option of having this treatment to avoid the potential guilty feeling of passing on this genetic abnormality to a child.
“This gives us the chance to eradicate this problem in families.”
Some critics say it is wrong to destroy embryos because there is only a chance women with the gene may develop breast cancer in adulthood. They argue that, increasingly, breast cancer can also be successfully treated.