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For good or evil: Genetic tests for the masses

GENETIC counselling is, as yet, in a primitive state in Britain. It
is usually left to doctors or nurses with no special training in dealing
with people in distress. Yet the task is to inform and support people faced
with making fundamental decisions about their own lives and those of their
children, when faced with sudden and unexpected information about their
genetic make-up.

The result of this medical monopoly on giving people ‘the bad news’
is that the much-vaunted increase in the scientific understanding of the
genetic basis of disease has often led merely to an increase in human suffering.

That stark judgment is supported by a recent study of pregnant women
undergoing prenatal tests that are designed to discover whether the fetus
has spina bifida or Down’s syndrome. In a project funded by the Medical
Research Council, Marie Johnston and Teresa Marteau of the Royal Free Hospital
in London uncovered the underside of current practice by charting the experiences
of women attending the hospital’s antenatal care clinic. Such antenatal
tests are not ‘genetic’ in the strict sense of tests for single-gene defects,
but they highlight the problems that are common to any attempts to screen
segments of the populace for faulty genes.

Of 900 women having blood tests for signs that the fetus may have spina
bifida, 71 tested positive. Further tests found only one genuine case. Those
70 women given a ‘false positive’ and later reassured were more anxious
and held more ‘negative attitudes’ towards the baby once it was born. The
researchers put these feelings down to ‘an inadequate understanding of the
test and poor preparation for potentially bad news’. For instance, a quarter
of the women tested believed that a negative result guaranteed that the
baby would be normal – and so received a ‘false reassurance’.

The use of medical language is another pitfall. Doctors readily talk
about a patient’s ‘risk’, for instance. Yet as Rayna Rapp of the New School
of Social Research in New York has argued, statistics is ‘an abstract mathematical
universe that most people do not share’. Johnston and Marteau tape-recorded
interviews between women and midwives and obstetricians. The recordings
showed that ‘very little information was provided to the women’. The researchers
conclude: ‘These findings underline the importance of educating staff as
well as patients.’ Moreover, the data emphasise that ‘a new discovery, such
as a gene probe, is just the first step on the way to an effective new clinical
³Ù±ð³¦³ó²Ô´Ç±ô´Ç²µ²â’.

This study is only one of a host of similar research projects that have
highlighted the failings of current medical practice. Doctors receive no
training in counselling or even in how to talk with people with backgrounds
that differ greatly from their own. They make classic errors – for instance,
telling somebody the bad news and then immediately going on to discuss the
various choices confronting them, when the person is too shocked to take
in any new information.

Much of the same problems surround the ‘counselling’ of couples undergoing
the new infertility treatments such as in vitro fertilisation. Nurses are
often pushed into counselling without any formal training in supporting
people in distress, says Jennifer Hunt, an infertility counsellor at the
Hammersmith Hospital in London. And as a key part of the medical team, nurses
can hardly be seen by anyone as truly ‘independent advisers’, she says.
Johnston and Marteau have found that couples trying to have test-tube babies
were ‘misinformed about the likely success rates and were unrealistically
optimistic about the outcome’.

Many working in both infertility treatment and human genetics now pay
lip service to the need for professionally trained, independent counsellors.
A committee set up by the King’s Fund, a health charity in London, is now
trying to thrash out what kind of counselling should be provided. But at
the moment few clinics actually employ such people. The striking success
of a London-based scheme for prenatal screening for the genetic disease
thalassaemia shows what is needed.

Bernadette Modell, a consultant in perinatal medicine, has pioneered
a programme at University College Hospital in London that offers genetic
tests for couples at risk of having children with a severe form of thalassaemia.
This disorder of the oxygen-carrying haemoglobin in the blood can be treated
only rather unsuccessfully by monthly blood transfusions and nightly injections
of an iron chelating agent.

People who are carriers for the thalassaemia gene – that is, have one
copy of the ‘faulty gene’ and one normal copy – are resistant to malaria.
So the gene is widespread among people living in the Indian subcontinent
and the Mediterranean, where malaria was once common. Trouble arises only
when a child inherits ‘thalassaemia’ genes from both parents.

Armed with this knowledge, parents who are healthy carriers may wish
to have prenatal tests, with the option of aborting afflicted fetuses. In
the Greek-Cypriot community in London, grassroots support for prenatal screening
is strong. Counsellors of the same ethnic background provide information
and support for couples at risk, and there is little if any social stigma
attached to people found to be carriers. ‘It is very important for people
who are carriers to realise that many other people are too, that they are
healthy, and that their genetic trait is advantageous – it confers protection
against malaria,’ says Modell.

But the disastrous failure of earlier attempts to screen people for
sickle-cell disease in the US shows how things can go terribly wrong. People
with sickle-cell disease have structurally altered haemoglobin molecules.
They are anaemic as a result, but the most serious problems arise because
the ‘sickled’ red blood cells block tiny blood vessels.

Again, inheriting two ‘sickle cell genes’ leads to the disease, whereas
possessing only one such gene has little effect. The altered haemoglobin
gene is most common in people of Afro-Caribbean descent. In the Nixon era
in the US, many states passed laws requiring black people to be screened
for the sickle cell gene. Employers and insurers began to use the genetic
trait as an excuse to refuse to employ or insure black people. The outcry
that followed led to the repeal of the laws and a deep mistrust of genetic
screening.

How can such abuses be prevented? James Watson, the director of the
NIH’s genome project, says we must simply legislate to make such discrimination
illegal. ‘There are some things about which we must simply say, you can’t
do it,’ he said at a recent conference on genetics at the University of
Leicester.

But society’s reaction to AIDS does not give grounds for optimism. Insurance
companies have reacted by first demanding HIV blood tests from all single
men and then denying life insurance and mortgages to those who are positive.
The ‘stark statistics’ make this policy good business, they say. But the
economics will be just as clear cut once genetic tests can reveal who has
inherited a predisposition to heart disease or cancer, now the major killers
in the West.

The notion of relying on the principle of ‘medical confidentiality’
has already proved a flimsy barrier to those who claim a right to know –
be they employers, insurance companies or the police. Those beavering away
at unravelling the secrets of the human genome have, by and large, yet to
take on board the implications this knowledge will bring.

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