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How Terahertz Waves Tear Apart DNA
KentuckyFC writes "Great things are expected of terahertz waves, the radiation in the electromagnetic spectrum between microwaves and the infrared. Terahertz waves pass through non-conducting materials such as clothes, paper, wood and brick and so cameras sensitive to them can peer inside envelopes, into living rooms and 'frisk' people at distance. That's not to mention the great potential they have in medical imaging. Because terahertz photons are not energetic enough to break chemical bonds or ionize electrons, it's easy to dismiss fears over their health effects. And yet the evidence is mixed: some studies have reported significant genetic damage while others, although similar, have reported none. Now a team led by Los Alamos National Labs thinks it knows why. They say that although the forces that terahertz waves exert on double-stranded DNA are tiny, in certain circumstances resonant effects can unzip the DNA strands, tearing them apart. This creates bubbles in the strands that can significantly interfere with processes such as gene expression and DNA replication. With terahertz scanners already appearing in airports and hospitals, the question that now urgently needs answering is what level of exposure is safe."
continuity of the state and its power structures is far more important than petty things like individual freedoms or human lives.
>>>People don't realize it, but our bodies birth cancerous cells constantly. We usually kill them off, though.
Yes but irritants (like tobacco smoke) create MORE cancerous cells, and therefore increase the odds you'll die of cancer. The solution is to avoid those things that encourage cancerous growth.
"I disapprove of what you say, but I will defend to the death your right to say it." - historian Evelyn Beatrice Hall
Actually, it's a theoretical explanation for some difficult experimental results. The issue was that some studies suggested that THz radiation would be harmful at any frequency/power range, while others pegged it as only being significant at particular resonant amplitudes or frequencies. It transpires that in the presence of thermal perturbations, you do indeed get some non-specific disruption of the base pairing, which would only be an issue if you had a long enough exposure to actually get a significant thermal perturbation and thus cause a very significant disruption. However there is also a resonant mechanism, at a particular frequency with a critical minimum amplitude, that can immediately cause a significant disruption, without the need to wait for a particularly big thermal perturbation. That's my reading, anyway.
No kidding!!! What do you say at this point?
Wait a moment, folk! We are talking about temporary separation of already uncoiled DNA (meaning, that it's probably under the process of being expressed, anyway) under very specific conditions as predicted by a computer model.
This is not even an empirical observation: we don't know that any of this happens in a cell free in vitro system and how significant the effect is (if any), we don't know if it happens in a cell culture in vitro system and how significant the effect is (if any) and we certainly don't know that anything like this happens in vivo.
Even assuming that you can create these precise conditions by an airport scanner (which seems rather doubtful), you certainly would not, in any way, be facilitating mutation in any appreciable sense*. All that you would be doing, theoretically, is to subtly alter patterns of gene expression for the few seconds it would take to walk through the scanner (basically, a very subtle regulatory effect). While you certainly can facilitate the development of cancer through such a mechanism (in fact, I'd argue that dysregulation of gene expression** at some points is simply required for carcinogenesis --yes, it can be caused by mutating proteins but these mutated proteins are almost invariably going to have direct or indirect regulatory functions***), such a dysregulation of gene expression would have be the prolonged, normal state of affairs of a cell for a cancer to actually happen. For this to be happening (in a worse case scenario) for as much as a few mere seconds can hardly even be called a dysregulation in any meaningful sense and much, much less have any effect, whatsoever, on carcinogenesis.
If, on the other hand, some government agency is monitoring you 24/7 with these scanners, then you might have reason to worry****.
* I would speculate that there's an infinitesimal chance that DNA might be more susceptible to mutations from not being as protected as it would be when paired but you have to realize that active regions of DNA get unzipped like this all the time so this effect, if it might be real, would be a drop in the bucket and utterly swamped by the background.
** For purposes of this discussion, what I mean by dysregulation of gene expression is the production of various protein products at inappropriate times or in the wrong amounts (either too much or too little of a protein).
*** Whether the function is to induce cell division or stop cell division, or to induce cell death (apoptosis) or to evade cell death (and whether it is a direct or indirect effect on the preceding --such as mechanisms sensing DNA damage, loss of contact inhibition, etc.). While other factors which may not always be strictly regulatory do exist such as invasiveness, angiogenesis, telomerase function, etc (which often will also be regulatory by involving over or under expression); these factors need to happen together with a regulatory dysfunction for an actual cancer to happen because, basically, cancer happens when a lot of different sorts of things get screwed up at the same time.
**** About adjusting your medication dose, that is.