But Dr George Williams, the retired Cheshire pathologist who did the post-mortem examination, said last night: "I'm utterly, absolutely confident of the authenticity of that material." The discovery, which will shock the Aids scientific community, casts serious doubt on current thinking on the origins of HIV and accepted wisdom on how the global Aids epidemic began.
Findings by American scientists after exhaustive and highly sensitive tests throw up two possibilities: either tissue samples were mixed up in a laboratory at Manchester University - something regarded as inconceivable - or the samples were deliberately switched. The scientists believe that tissue samples used by Manchester University researchers in the original analysis, published to world acclaim in the Lancet in 1990, were not from the 1959 patient but from an Aids victim who died about 1990. Virologists at the university claimed to have found the genes of HIV integrated into the DNA of tissue taken from the patient's kidneys, bone marrow, spleen and throat.
The case of David Carr, 25, an apprentice printer who did his National Service in the Royal Navy in the mid-Fifties before developing a mysterious illness in 1958, received world-wide publicity when the Lancet published what was then believed to be definitive evidence that he died in 1959 with HIV infecting his body.
He became "patient zero", the world's first confirmed case of Aids and the subject of intense interest to scientists anxious to answer two of the greatest mysteries of Aids and HIV: why did the global epidemic arise now and where did the virus originally come from?
However, for the past year a team led by Professor David Ho, an authority on HIV and director of the Aaron Diamond Aids Research Center at New York University School of Medicine, has repeatedly tried but failed to detect HIV in tissue samples taken from Carr's corpse. The samples were stored for more than 30 years in the pathology department of Manchester University.
When Professor Ho re-analysed the processed DNA allegedly from Carr which had been left over from the 1990 analysis and which was sent to him earlier from Manchester, the only type of HIV he could find was a strain that was prevalent in 1990. He has dismissed the idea that this HIV could date back to 1959. He has also confirmed that the samples used in the 1990 Lancet research came from a different person to the pieces of tissue sent to him last year - which were supposedly from Carr.
Professor Ho concludes that the authenticity of the research is not only in doubt but that there has been either a monumental mix-up or a deliberate switch of experimental material. "We even discussed wild ideas that someone intentionally provided us with a sample that just came from a contemporary Aids patient."
The discredited research appeared as a Lancet letter on 7 July 1990. Its authors were Dr Gerald Corbitt, director of the virology unit at the university's medical school, Andrew Bailey, his research assistant, and Dr Williams, who was responsible for keeping and retrieving Carr's stored tissue samples from the university's pathology department.
In their letter the researchers claimed to have found HIV in four out of six samples taken from Carr. They found no evidence of the virus in any of six tissue samples taken from a man who had died at the same time in a traffic accident, who acted as the HIV-negative control. "We conclude that the patient who died in Manchester in 1959 with an unexplained immunodeficiency and [lung disease] had HIV infection," the researchers wrote in the Lancet.
When Professor Ho was initially sent processed DNA in 1993, allegedly from Carr's bone marrow and kidney, he also found HIV. However, he became suspicious when he looked at the virus's DNA sequence, its genetic "signature". He was advised by Gerald Myers, director of the HIV Sequence Database at Los Alamos National Laboratory in New Mexico and an authority on viral genetics, that the virus was indistinguishable from HIV strains of prevalent around 1990. Dr Myers said it was inconceivable that this type of HIV could have existed more than 30 years ago because of the speed at which the virus mutates.
Professor Ho therefore asked Dr Williams for the actual tissue samples, rather than the purified DNA extracted from the tissues, to replicate the 1990 experiment for himself. Since February 1994 he has repeatedly tried but failed to detect any HIV, concluding that Carr's tissues were HIV-negative.
The unresolved question was how to explain the Lancet research and Professor Ho's discovery of HIV in the DNA allegedly from Carr's tissues which was sent to him initially from Manchester. He has discounted a simple laboratory "contamination" with stray HIV molecules and concluded that the tissue from which this genetic material was derived was genuinely infected with HIV but with HIV that was present around 1990, not 1959.
Last night he said the onus was now on Dr Williams to explain the discrepancy between the two sets of tissue samples: "It's a question of what happened to the first set of tissues and what happened to the second set. These are from two different individuals; only he would be able to answer the question." Asked whether there had been deliberate tampering with the evidence or a serious laboratory mix-up, Dr Ho replied that Dr Williams was "backed into a corner, where he has to choose between two very bad choices".
He also concluded that Dr Corbitt and Mr Bailey had isolated the same strain of HIV from genuinely infected tissue sent to them by Dr Williams. The Independent understands that both Dr Corbitt and Mr Bailey were unaware that the tissue they analysed was probably from an Aids patient who died around 1990.
The conclusion is that Dr Williams mistakenly gave contemporary tissue samples to the two virologists or that someone close to him had deliberately switched tissue samples to fool Dr Corbitt and Mr Bailey - and the rest of the world - into believing the tissue came from Carr's body.
Yesterday, Dr Williams said he stood by his results. "As far as the inference that these tissues come from different patients, that to me is impossible, because they were taken from that one case. It was the only case involved. I cannot understand this discrepancy." He dismissed the possibility that someone may have switched samples. "No. These tissues were paraffin-embedded, numbered and in their own confined file, so there's no possibility of that.
"We'll have to offer Ho further tissue. We should at least ask him to consider repeating it or get it done elsewhere . . . I'd be quite happy to supply material to anyone who would take it on. I just know that this is straightforward and authentic."
The American scientists' findings demonstrate that HIV is a new virus, one that has infected humans within the past few decades, rather than one that had its origins several centuries ago.Reuse content