Dear Dr. McDonald:
I will not try to convince anyone that PCR can be used successfully to specifically make multiple copies of any nucleic acid sequence that can be uniquely defined by two primer target sequences comprising the termini of the sequence of interest. The veracity of this no longer has anything to do with me. I think this has been confirmed by a huge number of laboratories around the world. The rapid spread of this simple technology would not have occurred had it been ineffectual or flawed in any persistent way.
The matter which you are considering, if I understand it correctly, is that the presence or absence of a given nucleic acid sequence, as determined by PCR, can be used as a reliable marker for a living organism in a biological sample. This is done quite often in scientific studies, but that does not mean there could never be exceptions. Remember scientific studies are done with the understanding that findings will be subject to scrutiny from colleagues. A nucleic acid segment very similar in size and terminal base could easily, in a cursory examination, be mistaken for the sequence in question. If this happened in the course of a normal scientific finding, somebody would finally notice it. Papers are retracted all the time. I am not aware of the nature of the evidence you are considering, but when it comes to legal issues, retractions dont necessarily make up for the original mistake, and if I were to offer advice to the courts system of Australia, I would plead that they realize that the AIDS/HIV issue is what is not settled scientifically, not the effectiveness of PCR.
I have enclosed a paper I published some years ago which encapsulates my personal opinion concerning the cause of AIDS. I represent a very small minority among scientists who have seriously considered this matter. Many scientific issues which are controversial are often decided in favor of the minority, by experiments. Some of the time the majority gets it right.
Prosecuting people based on an unproven hypothesis would seem to be unfair and rash. To cloak the real issues in a veneer of irrelevant technological detail is, in my opinion, a bit of a sham, unworthy of Australians.
Sincerely yours,
Dr. Kary B. Mullis
[Mullis also attached a 1995 Genetica paper entitled A hypothetical disease of the immune system that may bear some relation to the Acquired Immune Deficiency Syndrome]