Department of Medical Physics, Royal Perth Hospital, Western Australia, 6001,
Valendar F Turner, John Papadimitriou, Barry Page, David Causer, Helman Alfonso, Sam Mhlongo, Todd Miller, Christian Fiala
Send response to journal:
Nicholas Bennett and Montagnier's RT Activity
In his rapid response: "Re: One AIDS patient will suffice", 6 July, Nicholas Bennett wrote: "I refer back to a Perth Group paper published in the magazine Continuum in September/October 1996 where they state:
"(a) the presence of reverse transcriptase (RT) is proven indirectly, that is, by demonstrating transcription of the RNA template-primer A(n).dT15;
(b) the template-primer A(n).dT15 can be transcribed not only by RT but by other cellular DNA polymerases. All the cellular DNA polymerases, alpha, beta, and gamma, can copy A(n).dT15 (2). In fact, in 1975, an International Conference on Eukaryotic DNA polymerases, which included Baltimore and Gallo (3) defined DNA polymerase gamma, "a component of normal cells" (4), "found to be widespread in occurrence" (2) whose activity can be increased by many factors including PHA stimulation (5), as the enzyme which "copies A(n).dT15 with high efficiency but does not copy DNA well" (3);
it is impossible to say that the polymerase in the "growth medium" or in the material banding at 1.16gm/ml which catalyses reverse transcription of A(n).dT15 is RT or one of a number of other cellular DNA polymerases".
This they use as evidence that Montagnier didn't adequately prove that RT had been detected. In fact, as happens frequently in Perth Group articles I find, the evidence to counter such conclusions is to be found in the very references they use to support their argument, refs. 2-5 in the original article [2-5 below also], which I looked up some 5 years ago.
In summary: Montagnier's RT prefers Mg+ at 5mM and pH 7.8….The key word is PREFERS. DNA pol gamma will work with Mg2+ at pH 7.4, but Montagnier was careful enough to check they were the optimal conditions, and for DNA pol gamma they are not.
Additionally, DNA pol alpha does not transcribe poly A-Oligo dT, but early reports stated it did because of contamination with DNA pol gamma.
Montagnier also used further confirmatory methods, such as inhibition with Actinomycin D, which does not affect RT but does inhibit cellular DNA polymerases and RNA polymerases".
In his rapid response: Re "Where is the virus", 10 July, Nicholas Bennett wrote: "I also notice the conspicuous absence of Perth Group rebuttal to my criticisms of their RT argument: are they therefore willing to admit that Montagnier was successful in showing that RT and not any other enzyme was detected as banding at 1.16g/ml? Will they way whether this was due to a simple mis-reading of the original paper by Montagnier, a genuine mistake, or a deliberate omission to support their case? The statement about it being "impossible" to distinguish RT from a DNA polymerase when not only does a chemical exist (actinomycin D) but Montagnier actually performed this control, just demonstrates the Perth Group's inability to read the literature as well as their ignorance of molecular biology. Heaven forbid it was a deliberate attempt to mislead…." "
In our rapid response: "Montagnier's reverse transcriptase activity", 23 July, we wrote: "The detection of reverse transcriptase activity raises two questions: is the activity due to the enzyme reverse transcriptase and is the enzyme specific to retroviruses.
Montagnier's RT data was discussed in many of our publications as well as in our recent rapid response "Did Montagnier discover HIV in 1983?", 24 June. Here, suffice to mention that in the interview Montagnier gave to the French journalist, Djamel Tahi, at the beginning he stated that RT activity "is truly specific to retroviruses", then he said RT was only "characteristic of retroviruses". After further questioning Montagnier replied: "Taken in isolation, each of the properties [including RT activity] isn't truly specific".
In the paper entitled "Characterisation of the RNA dependent DNA polymerase of a new human lymphotropic retrovirus (lymphadenopathy associated virus)", Montagnier has reported that actinomycin inhibits the "HIV" RT activity "by approximately 50%".
In fig. 2 of the same paper evidence is presented that the cellular DNA polymerases b and g transcribe the template primer poly(A).dT15. The condition used included "pH 7.8" and "5mM MgCl2".
In summary: (a) Reverse transcriptases are not specific to retroviruses; (b) reverse transcription is not specific to reverse transcriptases; (c) in 1983 Montagnier reported reverse transcription of the template-primer An.dT in the "HIV" infected cultures but not in the non-infected cultures: this evidence was considered to prove viral "isolation"; (d) in 1984, using exactly the same conditions as in 1983, Montagnier reported reverse transcription of the template-primer An.dT in non-infected cells.
In his rapid response: "Re: "HIV", HHV-8 and KS", Nicholas Bennett wrote: "Through their repeated and circular responses without recognising the facts as presented to them, the Perth Group are clearly wasting the time of ourselves as well as those of the BMJ Rapid Responses editorial team. I echo Christopher Noble's response by asking whether the Perth Group are willing to admit that they were misleading when they said that Montagnier didn't properly characterise RT in the original "isolation" paper.
Their lack of honesty and the fact that their work is clearly influencing a small number of HIV-infected and uninfected people is potentially putting lives at risk.
As regards two of their questions to Chris Noble:
I have said REPEATEDLY that there is endogenous RT activity in cells, stimulated or not. However the Perth Group seem unable to recognise the principle of RELATIVE amounts. HIV infected cells produce many-fold higher amounts of RT activity compared to identically stimulated [non-infected] cells".
This is the first time that we have read (or heard) that the specificity of the retroviral reverse transcriptase can be determined on the basis of the "RELATIVE amounts".
Would Nicholas Bennett please tell us what is the cut off level above which the activity is due to "HIV" infection and below which is just endogenous cellular activity?
Competing interests: None declared