Unfortunately the second link will not load for me, but I'm assuming it's this article. Here's a pdf download of the full text.
I would like to see more info on this, especially which specific gene sequences the transposons were found in - but that will probably have to wait until whole-genome sequencing is cheaper.
I am not sure if it is prudent to speculate on such little evidence, but I would suspect that any useful effect these retransposons have on learning has to do with regulating the growth of dendritic spines.
And it is also possible that these are a deleterious element that we've just managed to mostly suppress the effects of, like P elements in fruit flies.
Still, the benefits and detriments of transposable elements in biology remains very much an open question, at least as far as I know.
If they are deleterious elements then instead of making cryonics harder, my bet would that it functions as another kind of "aging" that SENS would need to be able to fix in situ in order to achieve the grand vision of truly negligible senescence. My first thought in that direction is that you might need to create artificial work-alike "cells" to incrementally replace the ones whose DNA was becoming ever more infested with endogenous parasitic transposons... which sounds like a mature nanotechnological invention to me :-/
The thing is - they may have started out as a retrovirus infection, but now serve some important purpose. It's hard to say. Very butterfly effect-y.
Well, I wouldn't expect any very complicated stuff to be going on with the retrotransposons. It could be that it just uses this to store weights of connections by adjusting specific proteins, and that's all. Re-purposed unique binding ID proteins (forgot the biological term for it, each neuron makes itself entire series of more and less unique IDs).
Evolution is fairly slow and limited when it comes to inventing anything new. A mammal has never evolved 6 limbs even though it is fairly obvious that at least some niches had optimal number of limbs that's greater than 4.
If you need A to evolve B, and then need B to evolve C, and so on, it takes a lot of time as typically A would increase reproductive fitness only a little (say 0.1%), and would most often just die out due to random fluctuations. I recall reading an article about that, with all the relevant math done, i'll look for it later, but for now it is just fairly clear that for the most part mutations improve fitness only by very little, and the logarithm of number of mutants for small number of mutants just goes up and down like brownian motion with very slight extra force, usually crossing the 'extinct' threshold even though mutation was beneficial.
I would expect the human neurons to have very little extra 'DNA-computing' complexity versus a roundworm. I'd be very surprised if there's anything complicated going on beyond storing the weight of connections etc. I'd be very surprised if what's stored in DNA is not just the persistent store of how the proteins are at the synapses and what connections were and were not pruned and so on, the stuff we already know we need to be able to read. When I recall something, I am pretty sure I don't have to wait for the DNA or RNA to be read and proteins produced, and then for proteins to move around till they can latch onto whatever targets.
edit: So, assuming that DNA only stores duplicate of the data that's in the proteins at the synaptic junctions, this is good news and means that the brain scanning may be easier than we thought it is, as we found another place where we can read the data from. The brain emulation, I don't think that would make this harder to any practical extent.
It doesn't need to be anything complex. Perhaps just an neural activity statistics so that neurogenesis has information about where to put new neurons,
I generally think of this as a known unknown, I want more evidence that it is important before arguing too much. I think it just highlights that there might be unknown unknowns with regards to brain function, so our pdf for when ems occurs should be fairly broad.
Re-purposed unique binding ID proteins (forgot the biological term for it, each neuron makes itself entire series of more and less unique IDs).
Are you thinking about the immune system? If not I'd be interested in knowing more.
Yep, I think so too. Nothing in my reply to you right now may depend on the DNA directly as DNA is too slow; it has to use the already existing proteins which we already know we need to scan. Ditto for the 'long term memory'; long term memory write and recall cannot rely on this if you remember something from 3 minutes ago (which is still 'long term').
So, from a scan that does not read DNA we would have sufficient information to at least create the brain emulation that can write this reply; we may also need to figure out how retrotransposons work in the neurons to make the simulation accurate long-term (the emulation might otherwise end up with some kind of learning disability, potentially quite severe if the emulated brain can't retain long term memories beyond the span of several hours).
But I do not think we would absolutely have to find out a way to read the DNA off each neuron when making the scan. It would suffice to infer everything from the copy in the proteins. (however if we find a way to read dna of every neuron, it might be that we could use it instead of reading the proteins themselves accurately).
Are you thinking about the immune system? If not I'd be interested in knowing more.
The system that makes neuron not connect to itself.
edit: that's what i mean
Restoration. If you stop chemistry the dna should be intact to be read.
So it might take longer for the tech to be developed, which means it might be less worthwhile for you, if you think that humanity is unstable and may not look after you for that amount of time.
An interesting twist to the Turing test, someone might be behaviorally human and fool you in the short-term, but may seem odd when tasked with learning problems.
So, do you think we could make a Clive Wearing em?
Retrotransposons are small bits of genetic code than can copy themselves into other bits of the dna strand
They have been found to be active in brains, with different amounts of activity in different brain sections. The highest being in the hippocampus (an important region for long-term memory). Also they were active in coding regions.
"Overall, L1, Alu, and, to a more limited extent, SVA mobilization produced a large number of insertions that affected protein-coding genes,"
This means that they are more likely to have some large effect, than if they were just in junk dna.
One form of autism is linked to a malfunctioning of retrotransposons. So it can have a drastic affect.
It makes a certain amount of sense. If there is information in the brain that needs to to be stored, but not directly in neural firing rates, why not store it in the DNA of neuron? There is lots of error correcting data storage there and the genome has lots of tools for manipulating itself. Time will tell if it is very important or not.
If it is important, what are the implications for the future?
Cryo is harder, scanning the genome is a lot harder than just doing some spectroscopy. but since we assume a certain amount of sufficiently advanced technology and don't have a timeline, our plans aren't impinged upon.
The em scenario seems like it will take longer to happen or may have some gotchas. Being able to scan the genetic code of each neuron would require some serious breakthroughs in scanning technolgies.
To naively emulate the genetic code changes would take immense amounts of bandwidth and to crack things like the protein folding problem (for how the changes in ). Just for storage I think we might need on the order of 500 exabits to store the dna sequence for each neuron. You'ld need to update them as well, which is going to take lots of memory bandwidth. This is not to mention chemical emulation.
I think naive emulation of the brain is off the table before AI. We may well be able to do better with shortcuts in terms of ability. But there might be questions of whether the copy is "you" if short cuts are taken. Also if we understand the brain, we don't need to make copies of people, we could just create AIs that do the same thing.
Some even more blue sky speculation. If the changes in the genetic code are to do with changing how we learn, then it still might be possible to scan a brain at low res and get something that seems to act the same as someone else, but cannot learn in the same way. An interesting twist to the Turing test, someone might be behaviourally human and fool you in the short-term, but may seem odd when tasked with learning problems.
So call centre staff would be out of work, but scientists would be still in demand.
It also has implication on cloning attempts at intelligence amplification. I'm guessing this can be answered somewhat by looking at twins and the differential in mental ability between them. Anyone know of any books on this field.
Also anyone interested in discussion on this kind of topic (neurobiological implication on the future)?