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Star of the big screen

六月 21, 1996

Gail Vines meets Theresa Marteau, a health psychologist committed to exploring the consequences of giving people the information uncovered by genetic testing.

Talk to Theresa Marteau about the "genetics revolution" in that vague, slightly anxious way one does, and she's likely to say: "That's an interesting point, but it's an empirical question; it needs to be researched." Bioethicists may relish ex-cathedra pronouncements on the pros and cons of the genetic technologies waiting in the wings, but what Marteau wants is evidence.

Newly minted as professor of health psychology at the medical school attached to Guy's Hospital in London, Marteau is energetic, fun and only just fortysomething. She is "wonderfully singleminded", says Marie Johnston, professor of psychology at the University of St Andrews. "She can say 'now I am doing this and not that' which must be how she copes with work and partner and two young children." How old are they, I ask? "Not old enough," Marteau laughs, owning up to a daughter aged five and a son of eight. "The best thing, maybe the only good thing about this chair, is this," she tells me. "I said to my son, 'I'm going to be a professor', and he said after a while, 'But um professors are old men and they invent things'. His role model is Professor Calculus in TinTin, and actually, now I think about it, there are no female professors in children's literature I know".

Few female professors in real life either. Already, Marteau directs a dozen researchers set on exploring the consequences of telling people about their genes. Her Psychology and Genetics Research Group is one of just a handful of academic units in the world committed to empirical social or behavioural research on the "new genetics".

Marteau's was also one of the first. Well over a decade ago, she realised that something important was lurking on the horizon. Keen to ask psychological questions about genetic issues, she began to explore the ways in which health care professionals provide genetic tests, and what laypeople make of the test results.

With Marie Johnston, then at the Royal Free Hospital in London, Marteau applied to the Medical Research Council for funding to begin to look at the genetic tests on fetuses routinely being offered to pregnant women. "We wanted to look at women's views of the screening test for neural tube abnormalities and their reactions to it. We looked at health professionals too." It took a long time to get that grant, but they did eventually get it in 1986.

That landmark study documented "some of the emotional problems that arise from offering population-based screening programmes", says Marteau - particularly anxiety linked to "false positives", when test results wrongly suggest that a woman carries an affected child. But the study also showed that the women knew remarkably little about the tests.

"There are three main reasons why people don't have information," says Marteau. "They haven't been given it in the first place, they were given it but they didn't understand it, or they were given it, they understood but they forgot it." To discover the source of the women's ignorance, she tape recorded midwives and obstetricians as they talked to their patients. "What we found was that women were very often not given much information at all, and some of what they were told was inaccurate." No wonder, then, that the women did not know what the tests were for.

Published in the early 1990s, this study was "a watershed in terms of how we were thinking about what was going on". Marteau won another MRC grant to develop training programmes for the staff to try to teach them how to present information to women. The good news was that midwives and obstetricians improved their presentation skills after just an hour's training and by feedback on their consultations. The bad news was that most did not attend training, and that those who did were among the better communicators in the first place.

At about this time, Johnston left the Royal Free for St Andrews, leaving Marteau in an increasingly unsupportive environment. "I was on maternity leave with my second child and I wasn't going to get a locum, and I was being asked to double my teaching load when I went back. I had just got a grant from the EC and the MRC which I had to take up. I suggested to the dean that I couldn't do my teaching as well as my research load and he was not impressed by this. So that was a turning point."

Marteau began to work with the clinical geneticist Martin Bobrow at Guy's Hospital, and moved to Guy's herself, three years ago, with funding from The Wellcome Trust. They carried out a series of studies on the psychological impact of genetic screening programmes designed to detect healthy young adults who carry one copy of the cystic fibrosis gene. "Carriers" - about one in 25 Britons - are at risk of having children with cystic fibrosis if their partner is also a carrier for CF.

Are such widespread genetic screening programmes a good idea? Opinion is still divided in Britain. Many geneticists and obstetricians argue that such tests can enhance a couple's "reproductive freedom", enabling them to choose to have prenatal tests and to abort affected fetuses. But Marteau's earlier work on screening for carriers of another genetic condition, Tay Sachs, revealed unforeseen complications. Many people who were told they were carriers went away feeling more anxious and depressed about their future health, despite the fact that having just one copy of the CF gene does not make you ill.

Her timing was spot on. Marteau's findings were published in leading medical journals just as geneticists in Britain were pushing hard for full-blown screening programmes to begin. "After that, everyone was clear that the psychological cost of screening was a key issue," says Johnston. And thanks largely to Marteau's committee work, the MRC now requires that pilot screening programmes done on an "experimental" basis have psychological monitoring built into them.

The second of five children born to Catholic parents, she read social psychology at the LSE, and then trained as a clinical psychologist, pursuing an interest in psychopathology "more from an academic than wanting to help people point of view". Qualifying at Oxford she landed a post in the clinical department. But she grew frustrated by the work's limitations. "In a sense it's never ending; if you help one person there's another in the pile. I also felt increasingly that a lot of the problems that I was seeing were socially constructed, and that actually seeing people in that context was creating as much of a problem as it was solving. I felt too that I was losing touch with the discipline of psychology, and becoming a kind of barefoot helper."

When a psychiatrist colleague asked her to run a self-help group for parents of children with diabetes she found that "it was a real contrast looking at people who were dealing with a fairly difficult problem but dealing with it in such a positive way". With a grant from the British Diabetic Association, Marteau embarked on a PhD at Oxford in 1982, in the days when health psychology as a field had yet to be officially recognised in Britain. Her thesis is an exploration, even a celebration, of how people can view the same disease in different ways.

"The physicians who look after adults with diabetes keep saying to the paediatricians, 'you don't look after the children properly. You let their blood glucose levels go too high, and they get complications and we're the ones who have to pick up the tab on that'. But the paediatricians are trying to help the parents, particularly the mother, deal with the day-to-day task of keeping their child's blood glucose sufficiently high to avoid hypoglycaemia - so that they can play with their friends without the risk of becoming unconscious. So there is a misunderstanding born of a failure to appreciate the different contexts in which they find themselves. That was the message behind the work."

Marteau's group at Guy's now has a string of projects. Genetic counselling forms one research strand. "We are doing a large descriptive study first of all to see what's going on, with a view to going on to do an intervention study to try to train counsellors using techniques that would be more effective." Another project examines a newish screening test for Down's Syndrome, in which a sample of the pregnant woman's blood is analysed to pinpoint those deemed to be at high risk. "Most women will get a negative test result, and one of the big questions is, how do you convey that information? We have been randomising women to receive their results either as saying they are low risk for Down's Syndrome or to give them a probability of the risk, and looking at the trade off between false reassurance - 'I'm low risk, I'm no risk' versus excessive anxiety, 'I'm one in something'."

The problems of trying to communicate "low risk" information dogs carrier screening programmes too. At the time of testing, says Marteau, the people who get negative (that is, good) test results correctly understand that despite the "good news" there is still a risk, of about one in 135, that they carry a rare CF mutation that would be missed by the test on offer. But Marteau and her colleagues have recently discovered that, three years later, only about half of the people screened have retained that information. "Most of them are now seeing themselves as being at no risk."

More work needs to be done on false reassurance in all its guises, Marteau argues. To that end, her team has just begun a study, funded by the MRC, focusing on the experiences of the parents of children with Down's Syndrome. "We're comparing parents of 100 children born following negative results in screening, 100 who weren't offered it, and 50 who declined, and looking at how they have adjusted to the birth of the child," she says.

"There's a general question: is the widespread availability of screening leading people to expect that nothing will be wrong with the baby? Given that health professionals don't explain tests very well, many people are very unclear that they have had a specific test. So are people feeling cheated generally? Or are those with the false negative results more likely to blame, and so have more difficulty in adjusting, to the child? Or is giving birth to a child with Down's such a major event that the screening history pales into insignificance?" And what of the future? "I find it hard to see where genetic screening is going to go," she says. "At the moment we can articulate the problems pretty well, in both how staff are trained and how people process risk information, but we've barely made a start on finding ways of overcoming them."

With a sharp eye to the next genetic development on the horizon, Marteau is also investigating how people conceptualise inheritance and genes in the context of "multifactorial" conditions such as heart disease, diabetes, cancer and even traits such as intelligence. What will happen when people are offered gene-based forecasts of their susceptibility to disease? Are people going to flip straight over into some sort of genetic determinism? Or are they more sophisticated? And even if they do see genes as destiny, is there any way that you can give the information that would stop them from doing that?

Already some of the group's work suggests that talk of genes in a medical context can be counterproductive. A recent study by a PhD student in Marteau's team focused on an inherited condition known as familial hypercholesterolaemia. Parents who understand that their children had high levels of cholesterol in their blood were confident they could tackle the problem with diet and drug therapy. But those who had understood that a defective gene was to blame seemed much more fatalistic and felt there was little that could be done to help.

Yet Marteau and colleagues have also found that members of families at risk from the inherited bowel cancer FAP seem to resist thinking in genetically deterministic ways, despite their awareness of the fact that the cancer is a dominantly inherited condition linked to a single defective gene. "Even though they have been attending clinics and know quite a bit about it, they still conceptualise it as being a multifactorial condition," says Marteau. "It is not that they are ignorant, it's just that people have a sense that a gene may be necessary but not sufficient - there are environmental triggers. Scientifically I don't think it's that bad a way of thinking about it."

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