30 April 2007
ByAppeared in BioNews 405
UK doctors are applying for permission to help two couples avoid passing on hereditary breast cancer to their children. Paul Serhal, of University College London, has submitted a licence application to the Human Fertilisation and Embryology Authority (HFEA) to select embryos free from the BRCA1 gene mutation that causes the condition in their families. The case is one of the first of its type, following the HFEA's decision last May to allow the use of PGD for 'lower penetrance' mutations that do not always cause disease.
PGD involves taking a single cell from a 2-4 day old embryo, performing a genetic or chromosome test on that cell, and then returning one or two unaffected embryos to the womb. In the UK, the use of PGD is regulated by the HFEA, which licenses the procedure on a case-by-case basis. Previously, it has only permitted the use of PGD for fully 'penetrant' gene mutations that always result in a serious illness, usually in childhood. In contrast, women with mutations in the genes BRCA1 or BRCA2 face up to an 85 per cent chance of developing cancer in their lifetime, often in their thirties or forties.
The application follows a year of research by the UCL team, to identify the precise BRCA1 gene mutation that is triggering the disease in the patients' families. One of the couples being treated is reported to have lost three generations to breast cancer. Women who inherit a BRCA1 gene mutation are also at greatly increased risk of developing ovarian cancer.
The news has provoked criticism from Josephine Quintavalle, of pro-life pressure group Comment on Reproductive Ethics (Core), who told the Times newspaper that 'it is very likely that in the not-too-distant future there will be a way of treating breast cancer that doesn't rely on eliminating the carrier instead of curing the disease'. But Mr Serhal said that objections to carrying out PGD ignored the harrowing family histories of the patients he is seeking to help, who have a chance to ensure their children avoid similar experiences. 'You can have a preventative mastectomy, but this is traumatic and mutilating surgery that does not eliminate risk', he added.
The team is confident their application will be successful, as the HFEA has already approved the use of PGD for this purpose in principle. A spokesperson for the HFEA said: 'Each application for conditions such as this must be considered on a case-by-case basis because of the difference in the way that families are affected by these conditions'. It was revealed recently that another London clinic has applied for permission to use PGD to select embryos free from early onset Alzheimer's disease.
Dr Jess Buxton is Contributing Editor at BioNews and a Trustee at the charity that publishes it, the Progress Educational Trust (PET). She is co-author of The Rough Guide to Genes and Cloning (buy this book from Amazon UK) and Human Fertilisation and Embryology: Reproducing Regulation (buy this book from Amazon UK).