11 June 2007
freelance writer and co-author of 'Science and the Retreat from Reason'.
Appeared in BioNews 411The UK Draft Human Tissue and Embryos Bill, published recently, explicitly covers a number of uses of PGD (preimplantation genetic diagnosis). In this commentary I concentrate on just one - PGD to avoid diseases or disorders with a genetic component.
The Draft Bill proposes that a licence can only be granted for this purpose if 'there is a significant risk that a person with the abnormality will have or develop a serious physical or mental disability, a serious illness or any other serious medical condition'. (Schedule 2, 3 (2)). The wording follows the current Human Fertilisation and Embryology Authority (HFEA) Code of Practice. A number of factors to be considered in applying this rule are listed. Again, there is a close fit with the HFEA Code.
However, while the Code of Practice says that the views of the prospective parents concerning the meaning of 'significant' and 'serious' should be taken into account, the Draft Bill does not. This will be of concern to those seeking treatment. Ironically, given that one of the stated reasons for introducing a new law is to minimise legal challenges, if the Bill were to become law unchanged it might lay decisions in the field open to legal challenge, or it might make practice more illiberal and restrictive. The former might lead to the latter.
The current law does not explicitly mention PGD. In its response to the Government's consultation on a new law the HFEA called for it to do so. At the moment a combination of the HFE Act 1990 and a 2005 House of Lords judgement, Quintavalle v. Human Fertilisation and Embryology Authority, grants the Authority wide scope for discretion. The Court decision concerned the ability of the HFEA to license the creation of a 'saviour sibling' - the testing of embryos to determine whether a future child would be a tissue match for an existing ill child - but it had wider consequences. The Court stated that it was up to the woman to decide whether an embryo was suitable for her purposes, but that this did not mean that she could automatically expect the HFEA to license treatment. In principle this clarified that there was no impediment to PGD within the HFE Act while at the same time re-affirming that the HFEA had the power to refuse a treatment licence if it saw fit.
From a politico-legal perspective the obvious reading of this is that the Court was removing the possibility of future legal challenges (ie keep us out of it), without removing controls on what prospective parents could achieve through PGD.
That the 1990 Act made no mention of PGD might seem anomalous, and in some ways it is. But it is also a positive sign of the general support given to the wider practice of IVF at the time - embryo research was the more controversial issue and the subject of greatest debate.
Today, some writers argue that a plurality of views on the status of the embryo is justification for a limited restriction on individual choices in the use of PGD (1). The liberal view in contrast allows individuals to make choices, even if they upset others, unless real harms can be demonstrated. From this perspective I would suggest that it is not that the new Act should ignore PGD; rather, the opportunity should be taken to make it explicit that it is for parents to decide what disorders and diseases they wish to avoid through PGD, with no restriction in principle on the choices they can make.
Critics of PGD such as David King believe that harm does result from PGD - harm to people with disabilities. He made this argument strongly in his recent commentary for BioNews following the decision by the HFEA to grant a licence for PGD to avoid congenital fibrosis of the extraocular muscles (CFEM) (2). King does not provide any evidence for this harm, and I'm not sure how it could be investigated. He is perhaps on firmer ground in claiming that some people with disabilities take offence at the practice of PGD. However, he presents what seems to be an obviously absurd argument while making his case: 'if disabled people's perspectives are taken seriously, we would view far fewer genetic impairments as really being inconsistent with a worthwhile life, and therefore offer prenatal screening and PGD for a far narrower range of conditions than currently'.
In reality prospective parents and society do not see selection as being about avoiding conditions 'inconsistent with a worthwhile life' - in many cases they see it as a choice between two worthwhile lives, one of which would also be free from a known genetic risk or condition. I would be very surprised if the father-to-be in the recent case, who has CFEM himself, saw his life as not being worthwhile.
I also believe King to be wrong when he says CFEM is not serious. It substantially limits vision. But he does have a point in general about phrases such as 'significant' and 'serious'. They must mean something. Unless the phrases are entirely redundant in the context of the Bill the obvious implication is that some risks are not 'significant' and some conditions not 'serious', and that accordingly PGD for such conditions would not be allowed.
But why should treatment be refused in such cases? The threat of 'eugenics' is often wheeled out, or the motives of prospective parents seeking PGD are sometimes labelled 'perfectionist' (and this is considered grounds on which to restrict choice). In reality, what parents want to achieve through PGD is a healthy child; not a perfect child but a child free from a known risk. Why should there be any restriction on the genetic risk factors that can be excluded? In practice, taking account of all that is involved, there are many disincentives to using PGD, meaning that parents themselves are inclined to try to use it only for what they and many others would agree are serious conditions. But looking to the future, if a woman were already undergoing IVF and perhaps also PGD and was to make a request for a broader genetic screen, then why not? Evidence suggests that embryo biopsy does no harm to the future child, and IVF involves the selection of embryos as a matter of course. There is no 'slippery slope', just the hope of a slippery, slimy and healthy newborn baby.