Nobel Prize given to prion theorist

Whatever the mechanism of transmission of the spongiform encephalopathies such as BSE and CJD, it can be said with certainty that the properties of these diseases are very different to all others. High temperatures, ultra-violet light, and even radiation are all ineffective against them. The 1997 Nobel Prize for medicine has now been awarded to Stanley Prusiner, the scientist who explained this by proposing that proteins were the infective agents, rather than viruses or bacteria.

Since Prusiner developed this theory in 1982, it has come to be seen as the most likely explanation of the observed properties of these diseases.

The theory was a significant advance in the science of medicine. It challenged the long-held belief that DNA always had to be involved in the spread of disease.

As the Professor of Neurology at the University of California, Prusiner conducted experiments which appeared to show that material from an infected animal's brain could have all its components other than protein molecules removed, and yet would still spread the disease when injected into other animals. Prusiner's hypothesis was that the protein molecules being injected had changed shape. They then acted like a catalyst, causing proteins in the healthy animal to similarly change shape, until the build-up of the abnormal molecules caused the symptoms of the disease -- the most visible being the deterioration of the brain.

Although modifications have had to be made to the original "protein-only" hypothesis, and even Prusiner himself has had to admit that some form of genetic material may be involved, it is now widely accepted that the protein (known as PrP) identified as the agent by Prusiner is part of the process. A disease affecting yeast cells has since been found to spread in a similar way to prions, but with a different kind of protein mutating.

Research delayed

For many years, the study of the Transmissible Spongiform Encephalopathies or TSEs was restricted to a small number of very specialised scientists, whose terminology was not understood, even by other scientists. Those who studied the symptoms of the TSEs such as kuru were equally cut off from mainstream science.

Only when the epidemic of BSE began to take hold of the British cattle herd did this begin to change. As late as 1991, when BSE was already spreading very rapidly, proposals made by Prusiner for a programme of investigation into TSEs was turned down by the British authorities. He had planned to collaborate with Dr Gareth Roberts of St Mary's Hospital, Paddington, to determine the nature of the TSE diseases. His proposals were delayed by several years due to lack of funds.

Even now, when it is accepted by the majority of scientists that thousands will die from the human form of BSE, caught by eating beef from infected cows, there is no concerted effort to find a cure for these diseases. Instead, all the efforts of the incoming Labour government have been deployed to persuade McDonalds, Burger King, and the European Union to accept the infected meat and thereby increase the eventual death toll. Recent admissions that CJD could be spread by blood transfusions shows both the falsity of the claims that beef is safe once the brain and offal is removed (since it is now being accepted that the disease may be carried in the bloodstream), and underscores the seriousness of the dangers of an epidemic.

Genuine science dismissed

Those who conduct genuine scientific research into the nature of these diseases therefore deserve support. It is worth comparing the favourable coverage given to American Stanley Prusiner with that meted out to those working in this field here in Britain. Professor Richard Lacey has been effectively ostracised after warning of the dangers posed by allowing the sale of infected beef. Dr. Harash Narang was sacked and victimised after he claimed to have developed a urine test which could be used to determine how widespread BSE was amongst British cows. Many others have been starved of funds due to the political significance of their findings. They suffered because they were "too close to home" as far as the Ministry of Agriculture, Fisheries and Food, British politicians and the media were concerned.

While respected American scientists like Prusiner were not treated in the same dismissive way as their British counterparts, there were no places for them on the committees set up to advise the government on its handling of the BSE crisis despite their long track records of research into TSEs. They were seen as too difficult to lean on to toe the government's line. Instead the committees were filled with figures who had very little knowledge of the field, who could be relied on to "restore confidence," by distorting the scientific evidence and use their authority to downplay the dangers of BSE and CJD.

Much more research needed

The work by Prusiner is an important part of the effort by scientists to remove the veil of mystery surrounding the TSEs. It shows that consistent use of the scientific method can provide a solution to the BSE/CJD crisis. But the fact that Prusiner's work has yet to be either experimentally verified or refuted shows how much research has yet to be done on this life and death subject.

There are a number of weaknesses in the prion theory. Rival theories, such as Harash Narang's theory of a "nemavirus", can by no means be discounted. The main problem with the prion theory is the fact that there are about 20 different varieties of scrapie (the TSE which affects sheep) and it is difficult to explain how so many strains could result from deformations in just one type of protein molecule. This is explained in rival theories by proposing that the infective agent does contain DNA -- in the case of the "nemavirus", a single strand rather than the usual double-helix -- which would allow evolution to produce different varieties in the same way as for larger life-forms. The strands of prion protein would then be simply a product of the disease, rather than its cause as Prusiner claims.

Whatever turns out to be the truth, billions of pounds are needed to thoroughly research the nature of TSEs and find cures, firstly to eradicate the underlying infection still present in cows (despite the attempt to cover this up by killing the older cows before they show obvious symptoms) and even more importantly to save the thousands of human lives who will otherwise be needlessly sacrificed.

To investigate the reasons for the BSE/CJD disaster, and to show the need for a political struggle to open the way for such a solution, the Socialist Equality Party initiated the Workers Inquiry into BSE/CJD. The proposals put forward in its findings must be taken up by workers and scientists alike. These include:

1. Full compensation to the victims of CJD and millions to be made available to research the cause of BSE/CJD and find a cure. End MAFF's control over all BSE infected material. For all files and information on BSE/CJD to be made public.

2. An immediate ban on beef until every measure had been taken to ensure its safety. Full compensation and continued employment to be guaranteed to farmers and food workers affected, paid for by a sharp increase in taxes on big business.

3. The immediate reinstatement, without prejudice, of all those scientists and professionals victimised for speaking out. The removal from their posts of those scientists and civil servants who have been proved to be involved in the deception of the public.

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