oh this is getting interesting! Let me understand more. But first, I'd like you to answer: How do you define 'undamaged' in biology?
And is it true then that undamaged perfection --on the atomic level!-- is your and SENS holy grail? Is that what you're aiming at when you say that you want to stop aging?
Also, I'd like you to qualify: in your definition of damage, are the animals with negligible senescence 'damaged'?
Sorry for all these questions, but I'm sure that others would also like to hear the answers, to form a better idea of what SENS is all about.
Then, re you not approving of me calling SENS idea to 'preferentially kill' T-cell that specialize in herpes viruses stupid, would you please elucidate its wisdom, 'cause, as I pointed out earlier, this should cause the virus to not just flare up but to practically take over the host, as indeed I once saw. This, in my book, is not a favorable outcome. How would this strategy benefit the host?
Thanks niner!
Sorry for the delayed answer- I had a busy weekend. The kind of damage I'm talking about is at the molecular level. It means that bonds between atoms have been broken, or new bonds have been created where they shouldn't be, atoms have been removed, or new molecules have been attached to a biomolecule. In some cases, the damage doesn't interfere with function, so it doesn't really matter. In most cases, the body has ways to recognize and repair the damage. Most proteins are recycled on a regular basis, so even if they are damaged, they get replaced soon enough. Because DNA is so crucial, we've evolved numerous mechanisms to repair different sorts of damage, like strand breaks, mismatch errors, base dimerization and the like. One of the DNA repair mechanisms, when broken, is responsible for Xeroderma Pigmentosum, which is sometimes categorized as an accelerated aging disease. The relevance of molecular damage to aging occurs when we don't have a repair mechanism for a particular kind of damage, or the repair mechanisms that we have can't quite keep up with the rate that damage accrues. There are a few specific cases that are problematic. Elastin and collagen are extracellular proteins that get recycled very slowly if at all. They have coiled structures that kind of act like little springs- they are stretchy. AGE crosslinks slowly build up in these molecules, causing them to lose their elasticity. This leads to the classic sagging skin of aging, among other problems. If we could just figure out a way to get an enzyme or catalytic small molecule in there that would cleave the inappropriate crosslinks, we should be able to regain elasticity in our skin, blood vessels, and other sites. That's one of the things SENS is working toward. Others are described here.
The SENS Holy Grail isn't quite undamaged perfection, but rather to engineer fixes for the few cases where damage builds up due to missing or inadequate repair mechanisms. If we could remove enough damage to return you to the level of damage of a person in their twenties, that would be a spectacular success.
Animals with negligible senescence aren't completely undamaged, but their rate of damage accrual and repair mechanisms are matched better than ours are.
I don't think anyone wants to remove our ability to deal with all herpes viruses. The problem is that over time, CMV uses up a larger and larger fraction of Tcell memory reserve, I guess due to frequent epitope mutations, and we run out of capacity to deal with other threats. All those CMV-specific cells are useless because CMV is a relatively harmless infection- I guess there isn't much to fight. FightAging has an article on it here. It's not part of the main SENS program as defined here.
I hope this is helpful.