I was spurred to write this by reading the latest post on the Quackometer. Dr Luc Montagnier shared the 2008 Nobel prize for medicine or physiology, for the discovery of the human immunodeficiency virus, a discovery with a significant impact on our understanding of the evolution and spread of Acquired Immune Deficiency Syndrome (AIDS).
However, as the Quackometer notes, he's recently published in a different area. A rather strange area...
Earlier this year Dr Montagnier, along with several colleagues, published a paper entitled Electromagnetic signals are produced by aqueous nanostructures derived from bacterial DNA. (The term 'aqueous nanostructures' rings an alarm bell as it sounds awfully like some of the claims made about homeopathy.) The paper abstract states that
A novel property of DNA is described: the capacity of some bacterial DNA sequences to induce electromagnetic waves at high aqueous dilutions. It appears to be a resonance phenomenon triggered by the ambient electromagnetic background of very low frequency waves. The genomic DNA of most pathogenic bacteria contains sequences which are able to generate such signals.
The paper goes on to claim that these electromagnetic waves are associated with some unspecified 'nanostructures' in water (hence the title of the paper), & to suggest that these EM waves in some manner allow a re-creation of the microorganisms that originally produced them - even when the solution is so dilute that it can contain none of the original DNA!. This second claim seems to be based on the following finding:
filtration of a culture supernatant of human lymphocytes infected with Mycoplasma pirum, a microorganism of about 300 nM in size, through filters of 100 nM or 20 nM porosities, yielded apparently sterile fluid. The latter however was able to regenerate the original mycoplasma when incubated with a mycoplasma negative culture of human lymphocytes within 2 to 3 weeks.
Extraordinary claims require extraordinary evidence. And the first evidence I'd be looking for, with regard to the above quote, is absence of any possible sources of Mycoplasma contamination...
Anyway, you can see why I thought of homeopathy. Basically, this paper is suggesting that you can take the DNA from some pathogen, dilute it (with regular shaking at each dilution, and a thorough filtering after the first couple of dilutions) beyond the point where any of the original substance can be present - & somehow set up 'nanostructures' in the water that manage to emit particular EM frequencies that indicate the original presence of the pathogen. This is supposed to work for a range of different human pathogens, both bacterial & viral. Considering the differences in their DNA, I would have expected that - in the extremely (very, very extremely) unlikely event of this being a real effect - you'd expect to see differences in the EM waves detected. Tellingly, the authors report that the frequencies emitted are all alike, regardless of the bacterial species involved, although they do put this down to a lack of sensitivity in their equipment. (While I'm not a physicist, I do wonder about their equipment, & so did a number of the Quackometer's commenters - perhaps Marcus could say whether it would be capable of what's claimed for it.)
Now, there are a lot of questions that spring to mind about this paper. Why do only pathogens emit these EM waves? And only human pathogens, at that: why don't all microorganisms do it? What's more - as the Quackometer says - where's the evidence of any mechanism by which DNA could emit such radiation (given what's normally needed to generate radio waves)? Our chromosomes are not miniature radio transmitters.
If you've seen my earlier comments around reliability of sources, you'll also know that another question we should be asking is, who published this material? Science? Nature? The Quackometer reveals that the paper was published in the Journal of Interdisciplinary Sciences: Computational Life Sciences, 3 days after submission - which is a pretty clear signal that it wasn't subject to normal peer-review processes ie no-one's had a good critical look at the methodology & results prior to publication. Peer review isn't perfect, but it does help us to be fairly sure that the quality of the work being presented is reasonably good.
The worry here is that, because Dr Montagnier has done some excellent science in the past, and rightly been honored for it, some people will think that this latest bit of work is equally good. Indeed, one suspects that, somewhere, these results are already being put forward as an explanation for the supposed effects of homeopathy. Unfortunately they are no such thing - simply evidence that, while we can all be spectacularly right some of the time, we can also be spectacularly wrong.
PS Those interested in a more detailed analysis of the paper, including the methods used to obtain the claimed results, should read this post - & the comments - at Science-Based Medicine. (Thanks to Grant for pointing it out.)