Dr Myers dismissed the 1959 virus as an aberration”

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Published: July 27, 2010

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Dr Myers dismissed the 1959 virus as an “aberration”.Further evidence suggested that if this was a 1990 contaminant, it was no ordinary contaminant. For a start, Professor Ho had identified “quasi- species” of HIV in the initial samples sent from Manchester. This means the virus he had detected was present as swarms of slightly different forms, indicating it was a genuine HIV infection with multiple copies of actively replicating virus. It could not be a one-off contamination.Secondly, any accidental PCR contamination would be unlikely to result in an entire virus ending up in experimental material. Professor Ho was able to sequence the complete virus, which could only mean one of two things: either a complete clone of HIV had somehow got into the tissue sample or the tissue was genuinely infected with the virus.The former is most unlikely, he said, because few laboratories use HIV clones (and Dr Corbitt’s lab is not one of them) and in any case all sequences of such clones are known, and the sequence he determined was not from any known HIV clone in the world.This left the New York scientists with an uncomfortable conclusion. “Given what we’ve done now in the past few months we would think the initial sequence was incorrect or there’s been a sample mix-up … We even discussed wild ideas that someone intentionally provided us with a sample that just came from a contemporary Aids patient,” Professor Ho said.In summary, he concluded that the initial sample of genetic material from kidney tissue sent from Manchester was genuinely infected with HIV but that this virus was disturbingly similar to 1990 strains.

He faxed a note to Dr Corbitt in January 1994 saying how he was “greatly troubled” by the sequence. Professor Ho was so concerned that he decided to ask the Manchester researchers for the actual tissue samples themselves, rather than processed DNA supposedly derived from them, to see for himself whether they contained HIV. After several months delay, in February 1994, he received a set of nine tissue batches from Dr Williams and Dr Corbitt. Each was embedded in their original paraffin blocks.After an exhaustive series of tests using the most sensitive PCR tests available, however, he failed to find any evidence of HIV infection in any of the tissues, including kidney, throat, liver, heart, bone marrow, brain and pancreas.As a final check, Professor Ho employed a sophisticated DNA test to see whether this set of tissues all came from the same person – they did. However, when he compared them against the DNA sent to him earlier, he was shocked to discover that this HIV-positive tissue was from another person.

Furthermore, the size of fragments of a gene the scientists used as another check on their PCR technology indicated the two sets of samples from Manchester were from tissues of significantly different ages.The HIV-positive tissue generated large gene fragments, a clear indication it was recent tissue, whereas the second batch of HIV-negative tissue produced small fragments, showing the DNA had degraded, as it does in older tissue. Everything pointed to the positive batch coming from a 1990 Aids patient.The 1990 Lancet research had therefore failed the ultimate scientific test of its validity: replication by other scientists It will now have to be retracted. The tissues of David Carr appear after all to have been HIV negative and his fatal illness the result of another, unexplained cause. Mr Carr’s condition remains as much a mystery today as it was in 1959.Dr George Williams: the pathologistDr Williams performed the post-mortem examination on David Carr that determined the cause of death as pneumonia.

The first-named author of the 1960 Lancet paper describing Carr’s mysterious medical condition, he later discovered Carr’s stored tissues samples and presented them for analysis by Manchester University virologists. He retired three years ago.Dr David Ho: the Aids scientistHead of the prestigious Aaron Diamond Aids Research Centre at New York University Medical School, Dr Ho is considered one of the foremost Aids scientists in the world and helped to unravel how the Aids virus causes death several years after infection. Dr Ho performed the detailed analysis of the tissues samples from David Carr and found them to be HIV-negative.Dr Gerald Corbitt: Manchester virologistDr Corbitt is head of the virology unit at the University of Manchester Medical School. Along with his research assistant, Andrew Bailey, Dr Corbitt performed the analysis on the tissue samples sent by Dr Williams which found they were infected with HIV.

The three researchers wrote up the results in the Lancet in 1990 and received world-wide acclaim.Dr Trevor Stretton: the hospital doctorDr Stretton and his colleague Dr John Leonard were the two doctors in charge of David Carr on his admission to hospital in 1959. They were co- authors, with Dr Williams, of the 1960 Lancet paper that described Carr’s illness. Neither was involved in the subsequent tissue analysis that led to the 1990 Lancet paper. Both now retired, they keep an active interest in the case.Dr Gerald Myers: the HIV analystHead of the HIV Sequence Database at the Los Alamos National Laboratory in New Mexico, Dr Myers is considered to be the foremost expert in the study of HIV evolution.


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