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Prehistoric Gene Reawakened To Battle HIV
Linuss points out research published in PLoS Biology that demonstrates the reawakening of latent human cells' ability to manufacture an HIV defense. A group of scientists led by Nitya Venkataraman began with the knowledge that Old World monkeys have a built-in immunity to HIV: a protein that can prevent HIV from entering cell walls and starting an infection. They examined the human genome for any evidence of a latent gene that could manufacture such a protein, and found the capability in a stretch of what has been dismissively termed "junk DNA." "In this work, we reveal that, upon correction of the premature termination codon in theta-defensin pseudogenes, human myeloid cells produce cyclic, antiviral peptides (which we have termed 'retrocyclins'), indicating that the cells retain the intact machinery to make cyclic peptides. Furthermore, we exploited the ability of aminoglycoside antibiotics to read-through the premature termination codon within retrocyclin transcripts to produce functional peptides that are active against HIV-1. Given that the endogenous production of retrocyclins could also be restored in human cervicovaginal tissues, we propose that aminoglycoside-based topical microbicides might be useful in preventing sexual transmission of HIV-1."
Not from South America, if I remember correctly. There's a lot of genetic drift between American monkeys and monkeys found in Africa and Asia.
...and I know really it's too early to know, but the big question on my mind is: what sort of treatment are we talking about here?
Can a cure for AIDS be derived from this? Or will it be a matter of "if we catch an HIV infection early, we can clear it up and minimize the damage"? Or is it only useful as a preventative measure, which seems to be where the quote in TFS is headed?
If it's only useful as a preventative measure, then there are two big issues.
One is how prone it would be to user error. If it's a "follow these steps every time you're going to put yourself at risk" kind of thing, then there's a concern that the increase in people's willingness to put themselves at risk exceeds the practical efficacy of the prevention. OTOH, if it's a "go to your doctor once (or once every X time period) for a professioally-administered round of protection", then that's probably less an issue.
The other is... look, I'm all for scientific progress, and I think we should research the hell out of this, but let's not jump the gun. As evidenced by the fact that we call potentially-functional strecthes of DNA "junk", we do not understand what they do. If prehistoric animals used this sequence and we don't, there is probably a reason, be it small or large. Maybe it's as simple as "it takes cellular resources and the risk of an HIV-like attack had subsided below the break-even point" - and if that turns out to be the case, FULL SPEED AHEAD! Or maybe evolutionary pressures put the protein in disfavor because it interferes with some other aspect of modern human biology, or has some secondary effect that is harmful. Now it's hard to imagine that would weigh in as "more severe than an active HIV infection", so it might still be a useful treatment for a known case of AIDS if it can be used in that way (depending on cost/benefit vs. other AIDS treatments); but not necessarily a good preventative measure if that were to turn out to be the case.
Woah, I think I'm going to need a car analogy...
Say your car door doesn't have any manual door locks, since it was built to be all automatic, but you lost the remote a long time ago. Your car could easily be broken into or stolen, now that you can't lock the door. So, you have someone read through the engineering manual for the car to find the code the remote used, and build another one to let you lock the doors again.