Dilemma of kissing cousins

十月 27, 1994

The science of human genetics appears to be taking a "social" turn, with the blessings of Britain's biggest backers of biomedical research.

The Medical Research Council has begun to fund studies into the social and psychological implications of DNA technologies in the clinic, as part of its initiative on "genetic approaches to human health". The Wellcome Trust has also decided to support a "psychology and genetics" research unit at Guy's Hospital in London. The aim, says the MRC, is to discover "how best to introduce developments in genetics into routine clinical practice".

Thanks to these initiatives, the United Kingdom is "ahead of the rest of Europe and the United States in its moves to integrate psychological and social research into genetic screening programmes", says Theresa Marteau, director of the Wellcome unit at Guy's. To help set the research agenda, the MRC and the Wellcome Trust invited clinicians and social scientists to Abergavenny earlier this year to discuss "Culture, Kinship and Genes".

There is no denying the urgency of the issues. In time, the international scientific collaboration known as the Human Genome Project will reveal the genetic basis of thousands of human characteristics. This will make it possible both to detect, and to strive to eliminate, any gene deemed to be undesirable. Should anyone try? If yes, which genes -- or more accurately, whose, should be the targets? Many disease-causing genes are loosely linked to ethnicity. How should the new "genetic services" -- ranging from genetic counselling to genetic tests of individuals, couples, foetuses or embryos -- be offered to an unsuspecting public already riddled with racism?

Clinicians want to know how their services can best be made available to ethnic minorities who might be at increased risk of producing children with particular inherited diseases. Everyone carries potentially lethal genes, but ethnic minorities are often seen as presenting special problems for the delivery of health care. These difficulties tend to be regarded as predominantly "cultural".

At the Abergavenny meeting, Marilyn Strathern, social anthropologist at the University of Cambridge saw both advantages and disadvantages in the use of "culture" as an explanation for "difference". She argued that if British Pakistanis have "social and cultural backgrounds" to which genetic counsellors need to be sensitive, so does everyone. Moreover, she said, "we need to be alert to those situations where a selective interest in cultural difference actually makes it harder to take account of what people voice as a matter of judgement and reason".

Nor can the clinicians take refuge in biological definitions of ethnicity. "The boundaries of any ethnic group cannot be defined genetically", argued Helen Macbeth, a biological anthropologist at Oxford Brookes University. Take any gene and measure its frequency among groups of people worldwide: you will find no dividing line, no place where the gene is present on one side of the divide, and absent on the other. Instead, what you find is a continuous variation in the frequency of that particular gene. The gene that, in a double dose, causes thalassaemia, for instance, is more common among people from the Mediterranean and the Asian subcontinent, yet, the red-headed Macbeth added, even a Celt can carry the gene.

Social anthropologists were no more sanguine when it came to the delivery of genetic services. "I am extremely pessimistic about the ways in which concepts of ethnicity can be used," said Ursula Sharma, a social anthropologist at the University of Keele. The dangers, she argued, include the use of monolithic definitions of ethnic groups as an administrative way of controlling populations, as individuals are encouraged to define themselves primarily in terms of their "ethnic identity".

When clinicians set the research agenda, there is a danger of "cultural determinism", said Helen Lambert, a social anthropologist at the London School of Hygiene and Tropical Medicine. "The social scientist gives doctors 'practical' advice on gaining access to an ethnic group, which only reinforces the erroneous notion that a 'minority group' forms a homogeneous community," she said.

The risk of "culture-blaming", as ethnic groups are pathologised by the medical profession, is very real too, as the running debate about "consanguinity" at the Abergavenny meeting revealed. The argument focuses on British Muslims of Pakistani origin, who often marry their first cousins -- a form of "consanguinity". In family lineages that carry the thalassaemia gene, this marriage pattern may slightly increase the risk that the child will inherit a copy of the gene from both parents, and so develop the disease. But according to the Nottingham GP Nadeem Qureshi, clinicians may say to British Pakistani couples with an affected child: "Your child is abnormal because you are cousins" -- implying that the genetic disease is "caused" by traditional marriage.

Geneticist Bernadette Modell of University College London and her colleague Aamra Darr have striven to change such attitudes within the medical profession. Darr's work with British Pakistani families has shown that -- rather than condemn a system that provides strong social support particularly for women in the British Pakistani community -- doctors could use the strong kinship networks to convey information about genetic risks and promote prenatal diagnosis.

Yet health promotion campaigns are being launched to discourage first-cousin marriages, said Charlie Davison of the MRC's Medical Sociology Unit in Glasgow. "As an anthropologist I find it abhorrent."

One of the clinicians behind this recent medical campaign is Sarah Bundy of the Birmingham Maternity Hospital. She and her colleagues have noted the high infant mortality rate among British Pakistanis, compared to whites, other Asians or Afro-Caribbeans, and reasoned that "consanguinity" must be playing a part.

"One in ten Pakistani children are dying or severely disabled by the age of five," Bundy said. "I think this is sufficiently high for clinical geneticists to think they ought to go out and tell them." But the message that gets across is the "culture-bashing" one.

Nursing Times reported Bundy's work with the headline: "Nurses have a role in preventing first-cousin marriages", while the doctors' newspaper GP reported that "GPs struggle to keep cousins apart".

Darr sees genetic counselling of individuals and families as preferable to education campaigns aimed at the community. "Such schemes are damaging at the community level, because complex genetic information cannot be explained in that context." Modell adds: "Health education campaigns can be a substitute for services."

Elizabeth Anionwu of the Institute of Child Health, makes another point. "Rather than providing patients with information and support, whatever their decision, doctors are deciding what is right for people."

The consanguinity debate has now moved to Bradford, where Sue Proctor of the Bradford Health Authority and her colleagues are studying the impact of consanguinity on birth outcome in Bradford Pakistanis. The researchers are trying to weigh up not just genetic relationships but also "environmental" factors ranging from women's access to health care, housing, employment, diet and income. "Just because congenital abnormalities may be higher in related Pakistanis, it is wrong to conclude that a simple genetic explanation is right," Proctor says. The problem is that clinicians and media commentators may be reluctant to accept "poverty", rather than genetics, as an explanation.

Despite these dilemmas, medical geneticists stress the value of their services. For John Raeburn of the Centre for Medical Genetics in Nottingham, "informed consent" is the key. "Choice means everything," he says, "including the choice not to have screening." He fears that social scientists might argue that "couples asking for screening should not be allowed to have genetic tests, because of some untoward consequence for society at large. My concern is that there is a group of people who will not be catered for if we say genetic screening cannot happen".

Many social scientists at the Abergavenny meeting foresaw problems as genetic testing spreads. "Undirected" counselling may appear to offer free choice, for instance, but if screening is seen as a good thing and health a matter of individual responsibility, a subtle but powerful form of coercion can emerge socially. As a result, individuals who choose to reject genetic tests may one day be regarded as reprehensible.

The historian Chris Goodey also questioned the value judgements about suffering inhuman lives, as technology drives our thinking. Doctors screen for Down's syndrome and terminate affected foetuses, partly because it is technologically feasible, while the more basic assumptions underpinning this practice go unexamined. "No one with Down's has yet passed an A level, but does that amount to suffering?" Goodey asked.

Running through the conference were concerns about the tensions between clinicians and social scientists who venture into collaborative research. Anionwu said: "If the social scientists' findings challenge professional practice, what then?" Such issues need to be negotiated, argued Waqar Ahmad of the Social Policy Research Unit at the University of York. "Are we to have social science of or in medicine and health? I would be wary of too cosy a relationship with the medical profession. We need to maintain a critical outsiders' perspective, so we can detect the role medical ideology plays in the construction of people's choices."

Staking out the middle ground, Theresa Marteau spoke out against a "them and us" mentality. "The social sciences have been invited to contribute to research and policy formation," she said, "It is just the beginning of the behavioural/social agenda. We need to come back to the most pressing question: how to make decisions whether to use these technologies, and how best to do this." Marteau said she was optimistic: "Policy-makers want to fund in this area. I want social scientists to feel empowered -- not to hold hands with the geneticists, but at least to stay in the same room with them."

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