Many believe that genetic research offers a health utopia, but after the death of a patient on a gene therapy trial and the discovery of thousands more human genes, doubts have started to emerge. Jerome Burne reports
Genetic breakthroughs are announced almost weekly. Just last month, a major drugs firm announced it had found the genetic basis of migraine and psoriasis, while another researcher reported on links between genes and obesity. Such discoveries regularly promise to transform medicine and usher in a health utopia. Genetic diseases, it is claimed, will be vanquished, gene testing will detect who is a risk, new drugs will be created to suit individual needs, and even sequences of DNA will be modified if gone awry.
But a degree of caution is in order. Last month also saw some less optimistic announcements. In the United States, a major trial of a new gene therapy was terminated after the treatment killed a patient; and researchers announced that the generally accepted figure of 90,000 human genes was out by about a third - the true figure is probably 140,000.
With the human genome project scheduled to finish locating all our genes next year, an extra 50,000 has suddenly turned up. Could it be that this utopia is a little further away than anticipated? That is the view of James Le Fanu, health correspondent for the Daily Telegraph, who, in The Rise and Fall of Modern Medicine, claims that not only has the project failed to deliver any significant clinical benefit, despite 20 years of massive expenditure, but that it never will.
Even if it does, it may not create the kind of world we would want to live in, says Marshall Marinker, professor of general practice at the University of London. At an evening of talks on genomic medicine held at London's Institute of Contemporary Arts last month, Marinker warned: "These genetic discoveries could turn us all into permanent patients. Genetic markers of disease can be detected long before any symptoms appear. That could mean that illness is no longer a prerequisite of becoming a patient. Just the possibility that you may develop some disorder will be enough."
Another genetic luminary at the same session held up his hands to hype. "I think it is fair to say that the new genetics has been oversold," confessed John Sulston, director of the Sanger Centre in Cambridge, where the United Kingdom's human genome project is under way. "There is a convergence of interests between journalists wanting a good story and scientists wanting to talk up their findings to boost their own funding."
Sulston is not worried that the project will not deliver eventually. He believes the 30 per cent more genes is not a major problem. While finding the precise figure could take time, scientists already know how long a string of DNA is, or at least they know fairly accurately what it weighs.
"There are plans to combine the records of people's illnesses that the NHS holds with patients' genetic data," says Sulston. "That way we will be able to build up a detailed picture of what genetic types are most at risk from particular diseases."
In his book, Le Fanu does not share this optimism. Take, for example, the now badly tarnished notion of genetic engineering. Originally, this seemed a brilliant way to get pure human hormones for treatments, rather than relying on animal sources. You put the human gene that codes for a particular hormone into bacteria, which obligingly turn out human hormones.
In 1982, when Genentec announced it was going to use this technique to produce human insulin, the company became worth $80 million overnight. But 17 years on, the main product is still human insulin, which appears to be little improvement on the original animal product and is considerably more expensive. A couple of other genetically engineered drugs are useful for rare kidney and liver conditions, but it is hardly a new dawn.
However, Le Fanu's stance does not tell the whole story. "The new genetics will mean that the one-size-fits-all approach to drugs will disappear," Marinker says. "With most scientific trials, we know only that drugs benefit a group of people in general. Once we can match patients' genetic codes to the drugs that work for them, we will have a pharmacological revolution."
20 featuresThe Times HigherJNovember 26 1999 SPL DNA fragments showing chromosome 17, often associated with breast cancer The Times HigherJnovember 26 1999Features 21 But only time will tell whether the genetic revolution has been indefinitely postponed or is just running late.