"The welfare of the child is closely connected to the classical indication for PGD: a serious disease caused by a single gene mutation for which there are no, or limited, treatments, and, in most cases, presenting early in life. An example is an embryo that is homozygous for cystic fibrosis, where the child will definitely have the disease. In such cases it is inconceivable that doctors would agree to transfer these embryos as it would be at odds with their professional responsibilities."
However, as the use of PGD is being extended increasingly to conditions outside the classical range of indications, transferring affected embryos need not always involve a high risk of serious harm. This is obvious where treatable diseases are concerned, such as MCAD deficiency (where people with a faulty medium-chain acyl-CoA dehydrogenase gene are unable to metabolise fat, but can lead a healthy life by observing a strict diet).
"Things are less clear where PGD for hereditary cancer syndromes is concerned. Debate about this is urgent, as centres are already confronted with parental requests to transfer embryos found to have the targeted mutation (e.g. BRCA1 or BRCA2 genes for hereditary breast cancer) in cases where no non-affected ones turned out to be available. How should they respond? That there seems to be more room here to at least discuss the issue has everything to do with the nature of the conditions in question: serious but later onset, incomplete genetic penetrance (not all individuals with the mutation will also have the disease) and ava
|Contact: Emma Mason|
European Society for Human Reproduction and Embryology