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Suzi
Leather
Chair, Human Fertilisation and Embryology Authority
Selecting embryos gives
assisted reproductive technology (ART) professionals an awesome
power. How they exercise that power matters. It matters most for
the couples and children immediately involved. But how those selection
choices are framed is not only a matter for doctors and patients.
The general public which is concerned over genetic intervention
in plants and animals should be at least as concerned about intervention
in our own genetic nature. Interventions which link the characteristics
of one person to traits desired in another are particularly difficult.
The UK operates the
most liberal regulatory regime for ART in Europe, indeed probably
in the world. In this comparatively unrestrictive UK environment,
the Authority is permitted under the HFE Act to grant licences
authorising 'practices designed to secure that embryos are in
a suitable condition to be placed in a woman or to determine whether
embryos are suitable for that purpose.' Legal argument will of
course turn on what is meant by 'a suitable condition' or 'suitable
for that purpose'. It is rather clearer that this may apply to
embryos which are being tissue typed in the course of PGD, rather
than being tissue typed in the absence of PGD. As we have seen
it is perfectly possible for a legal ruling to go one way whilst
only months later a higher court overturns that judgement.
Until April this year
when the Court of Appeal confirmed the HFEA has a wide discretion
in this area, it was not clear that the Authority could licence
PGD and HLA tissue typing at all. At the time that the Whitaker
licence decision was taken, the HFEA had already been taken to
judicial review over the Hashmi licence. We have approached the
saviour sibling issue with caution. The Authority has set out
strict criteria for selecting embryos as matches for other people:
1. The condition of
the affected child must be serious or life-threatening.
2. The embryos themselves must be at risk from the condition by
which the existing child is affected.
3. All other possibilities of treatment and sources of tissue
for the affected child should have been explored.
4. The technique should not be available where the intended recipient
is a parent.
5. Only cord blood should be taken.
6. Appropriate counselling is a requirement.
7. Families are encouraged to participate in follow-up studies
and clinics are required to report the treatment cycles and outcomes.
8. Embryos may not be genetically modified to provide a tissue
match.
The second criterion
is perhaps most pertinent to tonight's debate: that the embryos
being biopsied should themselves be at risk from the condition
by which the existing child is affected. This criterion is not
there to express genetic solidarity. Rather, it touches on the
central issue of imposing risks without benefits in exchange.
Our policy on HLA matching has been criticised both for being
too precautionary and for not being precautionary enough. The
distinction between the Hashmi and Whitaker situations is complex
and difficult to communicate. But the Authority felt, as has the
UNESCO Bioethics Committee, that there is a fine and important
difference between the two situations. The risks and benefits
fall differently; and there is also the issue of managing uncertainty
or unknown risks.
Preimplantation genetic
diagnosis is comparatively new. It was developed to prevent the
transmission of serious sex-linked and single-gene disorders such
as cystic fibrosis, haemophilia and Huntingdon's disease. But
the majority of the several hundred cases that have been carried
out in the world so far have been to screen out embryos likely
to carry numerical chromosome abnormalities. Newer uses of PGD
in the United States include detection of mutations for susceptibility
to cancer and for late onset disorders such as Alzheimer's. And
the demand for using PGD does not stop there. Some people in the
USA request PGD to select the sex of their child for non-medical
reasons. I can understand why some people fear the slippery slope.
Scientific advances do give us opportunities to do what was once
unthinkable.
It is clear, I think,
that PGD can secure an outcome which is much better than the horrible
early death say, of an infant with Tay-Sachs condition. Clearly
then the resulting child benefits from the PGD to the extent that
it owes its serious-disorder-free life to PGD. But an intervention
which imposes risks without benefits, or where the benefits accrue
to another person, is very different. The evidence so far suggests
that whilst PGD damages and destroys some embryos, it seems safe
for those which develop into fetuses and subsequently into children.
But the truth is that considerably more evidence would be required
to rule out any long-term effects conclusively. So there is still
uncertainty. So until we have carried out large sample long term
outcome research we cannot really know what the risks are. What
implications does this uncertainty have for when genetic selection
techniques may be used? If the embryo to be biopsied is not at
risk of a serious genetic disease; if you are doing PGD simply
in order to benefit another person, is it acceptable that a child
should bear these unquantified risks in order to make it possible
to save the life of its sibling? Is this a just imposition of
risk?
Secondly, whatever
the risks of PGD with tissue typing eventually turn out to be,
even if there are none, HLA-matched siblings might be considered
a significant step further down that slippery slope towards designer
children. And just as we must be careful with the scientific developments
we must also guard our ethical boundaries. Simply because we can
do it does not mean we must do it. New technology simply gives
us more choices. In exercising that choice we should be cautious
about abandoning long-standing ethical principles; like not considering
people only as means, but always also respecting them as ends.
Thirdly, we should
consider the trajectory of these interventions. Natural conception
and IVF is, genetically at least, an uncontrolled, contingent
process which results in an unforeseeable combination of two different
sets of chromosomes. PGD with tissue matching or tissue matching
on its own both introduce an element of controllability or design.
Certainly this designing may be for good ends. But it takes us
into new inter-personal and family relationships. We are beginning
to make irreversible decisions about the genetic predispositions
of another person. Transforming an uncontrollable given nature
into a controllable character. Moving our nature, some might say,
from the 'grown' to the 'made'.
Is this hyperbole?
We are, after all, only selecting: we are not engineering. True.
But we know that in plant and animal husbandry, selection preceded
manipulation. Both scientifically and rhetorically. Indeed, a
common argument in favour of GM is: 'look we've been altering
genomes for years with selective breeding. What's new about genetic
engineering?' Already there have been some notable scientists
who have claimed that intervening in our children's genomes can
'cure' ugliness and stupidity. It's not surprising then that the
Parliamentary Assembly of the European Council has argued for
'a right to a genetic inheritance immune from artificial intervention.'
The difficulty is in
separating the selection of undesirable hereditary factors from
the optimisation of desirable ones. And when the potential risks
of doing PGD fall on one child and the benefits on another, the
moral calculus is also horribly difficult. There is the child
in the family waiting for a tissue-matched transplant. It seems
so easy simply to have a sibling as a donor. So does it matter
if we cross the Rubicon: if we deliberately entangle one person's
existence with another's purposes? What might be the impact of
knowing you owe your existence to serving another's purpose, however
laudable? We speak of 'saviour siblings': words with a messianic
ring. We might equally speak of 'spare part sisters' or 'bred
to order brothers'.
In fairness, the decisions
we make for one couple we must make for all in that position.
What would institutionalised PGD with HLA matching look like?
What would be the public health goals or aims of PGD with HLA
typing? I wonder if this private solution to the need for more
matched donor tissue actually has a public solution: a properly
recruited and resourced cord blood bank. If we had comprehensive
cord blood banking would this be preferable? Would it for instance
avoid pressure on future women to have babies to save other children?
We know that having another baby will not be possible for some
women. Would it be a preferable option for the selected children
who may feel under pressure to go on being donors for their siblings?
If the cord blood donation doesn't work, what about a bone marrow
donation later? How many?
As a robust regulator,
the HFEA will keep HLA matching under constant review. We will
study the evidence, listen to public opinion. These uses of PGD
are very far from the ART interventions which Parliament had in
mind when it passed the legislation in 1990, and I believe that
it is time we revisited that legislation and time this was decided
democratically and collectively. I don't think we should not allow
these questions to be left only to a handful of clinicians. The
lines we draw warrant public not private endorsement or rejection.
And this is one of the reasons why meetings like this tonight
are so important.
I think that the central
issues for tonight are these: In the absence of real knowledge
about the risks of doing PGD and tissue typing, how precautionary
should we be about applying it to embryos when the benefits will
not be principally for the child who develops from that embryo,
but for another? And
secondly, do we want a world in which adults can treat the desirable
genetic traits of their descendants as something they can shape
according to a design or model of their own liking? And if we
do, what are the limits we should set on that choice?
Copyright Progress Educational Trust
This transcript cannot be reproduced without prior permission.
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