I've been reading a bit about biology lately, and I've got this question. Basically, my idea goes something like this:

1)Each organism, down to cells, has a DNA that defines it(I know not all organisms do, bare me on this)
2)It is beneficiary, for every organism, to "evolve", that is make beneficiary variations to its DNA
3)the DNA is copied by some enzymes
4)The enzymes themselves are coded too inside the same DNA chain
5)Now, if an organism had, in its DNA, enzymes that would be able, by themselves, to apply certain variations in certain parts of the DNA, for the benefit of the whole organism, then that would help the organism in the process of natural selection.

It got me the idea that it is possible, based on all this, for the enzymes themselves to "evolve" to a stage where they perform certain variations on the DNA, when they copy it, besides the usual "random mutation". Some kind of "recursive evolution", so to speak.

What do you think about it, is this idea floating somewhere in the biology science so I can read more about it?

I've been reading a bit about biology lately, and I've got this question. Basically, my idea goes something like this:

1)Each organism, down to cells, has a DNA that defines it(I know not all organisms do, bare me on this)
2)It is beneficiary, for every organism, to "evolve", that is make beneficiary variations to its DNA
3)the DNA is copied by some enzymes
4)The enzymes themselves are coded too inside the same DNA chain
5)Now, if an organism had, in its DNA, enzymes that would be able, by themselves, to apply certain variations in certain parts of the DNA, for the benefit of the whole organism, then that would help the organism in the process of natural selection.

It got me the idea that it is possible, based on all this, for the enzymes themselves to "evolve" to a stage where they perform certain variations on the DNA, when they copy it, besides the usual "random mutation". Some kind of "recursive evolution", so to speak.

What do you think about it, is this idea floating somewhere in the biology science so I can read more about it?

I think I read about a bacteria that could take DNA from other organisms and weave it into it's own but breeding generally replaces the need for something like that or what you are talking about and would likely have better results.

breeding generally replaces the need for something like that or what you are talking about and would likely have better results.

Breeding works better on a species basis, but something like this would be more on a per-organism basis. Imagine if your body got better at repairing itself as you aged.

I remember hearing a TED talk on a guy that thought it was realistic within 4 generations to have the biological understanding to have humans that would be able to live naturally forever. His concept had to do with all of the problems that happen in later life happen because the body gets worse and worse at repairing itself and the little issues build up until there is a catastrophic failure. If we were to both prevent the small problems from happening at such a rate and go in and perform regular maintenance on the problems that did happen sooner we would be able to increase our lifespans to such a degree that any further problems that might come up would be easily solvable inside the new lifespan (IE living forever).

here: http://www.ted.com/t...void_aging.html

EPIC. BEARD.

I always find it amusing when people refer to evolution as a voluntary process for the "benefit of the organism," rather than just a random event that it really is. It's natural selection that makes sure only the "beneficial" evolution persists, and all the "mess ups" die off.

The only thing evolution acts on is a [color="#1C2837"]species not individuals. Telomeres are the main reason for people aging and fixing them will just cause cancer. So really the solution to aging is a cure for cancer though very ironic...

[quote name='SteveDeFacto' timestamp='1296736613' post='4768978']
breeding generally replaces the need for something like that or what you are talking about and would likely have better results.

Breeding works better on a species basis, but something like this would be more on a per-organism basis. Imagine if your body got better at repairing itself as you aged.

I remember hearing a TED talk on a guy that thought it was realistic within 4 generations to have the biological understanding to have humans that would be able to live naturally forever. His concept had to do with all of the problems that happen in later life happen because the body gets worse and worse at repairing itself and the little issues build up until there is a catastrophic failure. If we were to both prevent the small problems from happening at such a rate and go in and perform regular maintenance on the problems that did happen sooner we would be able to increase our lifespans to such a degree that any further problems that might come up would be easily solvable inside the new lifespan (IE living forever).

here: http://www.ted.com/t...void_aging.html

EPIC. BEARD.
[/quote]

[color="#1C2837"]The only thing evolution acts on is a [color="#1C2837"][color="#1C2837"]species not individuals. Telomeres are the main reason for people aging and fixing them will just cause cancer. So really the solution to aging is a cure for cancer though very ironic...[color="#1C2837"] Also btw I actually watched a documentary about Aubrey de Grey and he actually has a PhD in Computer Science and is now working on his Biology degree mainly because he married an older woman who has a PhD in Biology. I think he is a smart dude but I also think he is mainly studying this because he is chronically scared of death.

[color="#1c2837"]The only thing evolution acts on is a [color="#1c2837"][color="#1c2837"]species not individuals. Telomeres are the main reason for people aging and fixing them will just cause cancer. So really the solution to aging is a cure for cancer though very ironic...[color="#1c2837"] Also btw I actually watched a documentary about Aubrey de Grey and he actually has a PhD in Computer Science and is now working on his Biology degree mainly because he married an older woman who has a PhD in Biology. I think he is a smart dude but I also think he is mainly studying this because he is chronically scared of death.

I wouldn't be surprised if that were his reason for studying it.

I know that "evolution" only acts on a species, but if you view each human's different cell types as their own species of cell types it should work similarly. The problem comes from what is best for the cell to replicate more is not always in the body's best interest (cancer).

In a sense, the perfect solution is selectively controlling the "evolution" of the cells in our body to replicate in such a way as to reduce waste and make more desirable copies of themselves.

Evolution is in quotes because it's not really evolution as it's not on a species, but it is still very similar to how evolution works.

I know that "evolution" only acts on a species, but if you view each human's different cell types as their own species of cell types it should work similarly. The problem comes from what is best for the cell to replicate more is not always in the body's best interest (cancer). In a sense, the perfect solution is selectively controlling the "evolution" of the cells in our body to replicate in such a way as to reduce waste and make more desirable copies of themselves. Evolution is in quotes because it's not really evolution as it's not on a species, but it is still very similar to how evolution works.

Not really. The definition of evolution is a change in gene frequencies in a population. Since each cell in a human body contains the entire genome of that person, the gene frequency cannot change. And since cells collectively make up an entire organism, we can't really evaluate the cost/benefit of cellular reproduction on a per-cell basis. But as you said, you know it's not evolution in the truest sense. Assuming that I understand your position correctly, here are my thoughts:

If you're talking about causing/preventing individual (or even types) of cells' reproduction, that's not handled directly at that cell's level. There are already a lot of checks on when a cell will reproduce, in which if conditions aren't appropriate reproduction won't take place. There are certainly failures in this process (like cancer, as you mentioned), but this is the result of degradation of the genes that prevent unchecked cellular reproduction. The control is already there-- it's the failure that we need to address, not the overall control mechanism. It's hard to prevent this degradation from occurring, as statistically some copy of a given cell will contain an ineffective control structure, due to mutation or telomeric degradation or other reasons, eventually.

And copies of cells are remarkably faithful to the original, in functional terms. DNA copying is a mechanical process, and has a well established failure rate (something like 1 in 10,000 base pairs). Since 90% of the human genome codes for nothing, the majority of these failures don't have any effect on the function of the cell. But in cases where a critical portion of the DNA is not copied correctly, there are autolytic controls that cause the malformed cell to die on its own.

Finally, evolutionary pressures are unlikely to operate on the cellular scale of an organism. The success of a cell's ability to reproduce has little to do with the cell itself. The organism that contains the cell provides ample resources for reproduction, as well as protection from "predators", and so on. And no matter how well or poorly cells perform, the death of the organism results in the death of all cells. This also ends the lineage of those cells forever, with the exception of organism-level reproduction, which has several obstacles to the level of fine-tuning described above.

To the OP, the biggest issues with the idea are that

1. Enzymes are mechanical, and can't exercise will or intention. If molecules fit into the active site, they are operated upon by the enzyme. If not, nothing happens. You can have different types of enzyme for different tasks, but enzymes themselves rarely do much more than one task. So an enzyme will do one thing, one way. You can randomly alter an enzyme by changing the DNA that codes for it, but...

2. Genetic information is extremely dense and complex. A change of any sort in a coding region of DNA is at least as likely to be harmful as beneficial. If you look at the four levels of protein organisation you'll see that a random change can easily ruin the entire protein and stop it from not only doing anything useful, but anything at all.

3. Organisms don't like genetic material too different from its own. When people get organ transplants, there are serious histocompatibility issues, and the recipient needs to take immunosupressors for the rest of his or her life to stop their own immune system from killing the foreign organ. If you have enzymes changing DNA all the time, the immune system will attack the altered cells ferociously, and people would exhibit symptoms of autoimmune disorders, like lupus or MS. So there isn't too much wiggle room for variation in the genome of a single organism, regardless of whether or not a given change is beneficial.

4. The three points above wouldn't be much of a problem at a species level if the reproductive rate were high enough (bacteria and viruses almost never have any error checking capacity in their genetic material, and have a much higher rate of copy failure than eukaryotes). This produces lots of crazy variations, but the vast majority of mutated organisms are either functionally very similar to their progenitor or not very fit.

There's a novel called Xenocide by Orson Scott Card (third in a series) that deals a lot with the kind of idea you've got, but it's science fiction.

EDIT: Geez, the quick-edit feature reduced all of my post to a single block of text! I'll have to remember to use the full editor.

I always find it amusing when people refer to evolution as a voluntary process for the "benefit of the organism," rather than just a random event that it really is. It's natural selection that makes sure only the "beneficial" evolution persists, and all the "mess ups" die off.

I think you misunderstood me. I know it's random and not voluntary. What I'm saying is, if it is at all possible that copy enzymes have evolved too based on this "randomness" and natural selection. That is, imagine at some point that the enzyme responsible for copying part A of gene B of DNA worked as usual, with the only "copy errors" being random and not following any pattern. At some point(s), the DNA part that encodes the enzyme itself gets mutated the same way, randomly, and causes that enzyme to make errors in the copying, not due to external factors, but as an inherent trait. That is, it is encoded in the enzyme to copy, say, G instead of T, 0,1% of the time when copying a specific part(I mean, more than usual). If one, or some, of those hardcoded errors(mutations) in the copying were beneficial to the organism, or to the gene, exactly the same way as mutations due to purely random and external factors are, then the mutated copy enzyme would continue to multiply in the gene pool, just as all DNA sequences that mutated purely randomly are. That's all I'm wondering. Maybe I implied that this process could take effect in a single organism, but really I'm wondering more on a species basis.

Finally, evolutionary pressures are unlikely to operate on the cellular scale of an organism. The success of a cell's ability to reproduce has little to do with the cell itself. The organism that contains the cell provides ample resources for reproduction, as well as protection from "predators", and so on. And no matter how well or poorly cells perform, the death of the organism results in the death of all cells. This also ends the lineage of those cells forever, with the exception of organism-level reproduction, which has several obstacles to the level of fine-tuning described above.

I am aware that it doesn't happen as it stands now (probably in large part due to our relatively short lifespans among other things). I was mostly talking about finding ways to perhaps trigger our cells to "evolve" in desirable ways so that as you get older your body performs and repairs itself better. Trigger isn't exactly the best word I'm looking for I just can't think of the right one atm. This is all pie in the sky wishful thinking, but I could see a world where that would be something achievable.

I would consider cancer a sort of cellular "evolution". The cell starts rapidly producing, which is advantageous considering its environment where resources are generally abundant. It results in the eventual death of the human, but on a cellular level it has become the dominant cell. The problem is that the cellular evolution isn't aware of how it affects the organism as a whole.