Doctors at University College London have performed the first procedure in the UK to screen out a genetic abnormality which is linked to breast cancer.
The BRCA1 gene, when properly functioning, can help prevent breast cancer - but abnormal variations can significantly increase the risk of developing breast cancer. Females born with the affected gene face a 50-80 per cent risk of contacting breast cancer. In 2006 the UK's Human Fertilisation and Embryology Authority (HFEA) permitted fertility clinics to perform PGD (preimplantation genetic diagnosis) - a procedure whereby embryos are tested for various conditions, the healthy ones are re-implanted and those that are affected are discarded - to test for this type of gene that makes carriers susceptible a disease but not necessarily leads to disease in all cases. BRCA1 and BRCA2 account for around five per cent of breast cancers and it is thought roughly 37,000 women in the UK carry BRCA1.
Paul Serhal, at the University College London, performed PGD to screen the embryos of a 27-year old woman, who wishes to remain anonymous, late last year to ensure that her chid will be unaffected by the inheritable condition. Even if the child is a boy, he can act as a 'carrier' and the affected gene can be passed to future generations. The child's father's family had been affected by the disease with women in three generations being diagnosed with breast cancer in their 20s. The screening means that the gene will not afflict future generations of the couple. 'The whole objective of this exercise is not just to make sure the child doesn't have the gene, but to stop the transmission from generation to generation,' said Mr Serhal. The procedure will not guarantee that the child will never contract breast cancer, however, for there are other genetic and environmental factors that can lead to the disease.
There are some ethical concerns surrounding the procedure as because women with BRCA1 may not develop breast cancer, it involves discarding embryos which may otherwise have led lives unaffected by breast cancer.
Dr Alan Thornhill, of the London Bridge Fertility Centre, welcomed the news saying: 'While the technology and approach used in this case is fairly routine, it is the first time in the UK that a family has successfully eliminated a mutant breast cancer gene for their child... It is a victory for both the parents and the HFEA that licensed this treatment'.