Plants May Be Able To Correct Mutated Genes

ddutt writes "NY Times is running a story that talks of an exciting new discovery, which, if confirmed, could represent an unprecedented exception to Mendel's laws of inheritance. The discovery involves.. 'plants that possess a corrected version of a defective gene inherited from both their parents, as if some handy backup copy with the right version had been made in the grandparents' generation or earlier.'"

Re:How this impacts evolutionary theory

[filmmaker]

Unfortunately, that will be the major headlines coming across the Fox News screen..."Evolution flawed: mutations don't occur. Jesus weighs in on Bill O'Reilly tonight!"

But the reality is that they don't know what causes this, they don't claim that it stops mutations on the whole, and they don't know if it stops all mutations. As per the article, it may only stop harmful mutations.

Re:How this impacts evolutionary theory

[cot]

This would only be true for these specific plants and only if this mechanism ALWAYS prevented mutation.

If these conditions applied to us, we wouldn't have cancer.

Perhaps it's a result of evolution

[PornMaster]

DNA containing redundancy certainly isn't efficient, so perhaps it's something that happened *because of* evolution, and doesn't negatively impact evolutionary theory, just requires that we modify our understanding of it.

Makes Sense

[latent_biologist]

Most Plant genomes are crazy complex. Besides that, polyploidy is often the norm [ncsu.edu] in plant chromosomes. With that much genetic material to work with, i guess you'd be bound to find a 'do-over' someplace.

Re:Makes Sense

[GAATTC]

If you read the actual article, you will find that: - The research was performed in Arabidopsis, which behaves as a diploid - There are no other copies of the hothead gene which could have corrected the mutant copies There is something more complicated going on here

Re:How this impacts evolutionary theory

[jazman_777]

But the reality is that they don't know what causes this, they don't claim that it stops mutations on the whole, and they don't know if it stops all mutations. As per the article, it may only stop harmful mutations.

I expect a long series of posts detailing a lot of thought experiments and speculations on how exactly evolution uses this, many outright contradictory, none observed. Just more Evolution of the Gaps from the Crowd of Lawyer-Wannabes.

Re:Makes Sense

[D3]

Yes, but this was seen in Arabidopsis (Mustard plant) which is not a polyploid plant. The article states that when they checked the genome there were no other "good" copies of the gene available to revert to. Both copies of the gene (one from each parent plant) were mutated copies. Yet somehow the DNA got reverted back to the non-mutated "grand-parent" copy in about 10% of the plants.

Re:How this impacts evolutionary theory

[thefirelane]

it may only stop harmful mutations.

Granted, I have just an armchair knowledge of evolutionary theory... but isn't that a little off point? I thought the point of evolution was the organism doesn't know which mutations are harmful, many are tried, and the ones that work survive.

Re:How this impacts evolutionary theory

[rob_squared]

Exactly, science doesn't work like that. If a part might be, or is, wrong, that doesn't invalidate the entire theory necessarily. Evolution is somewhat like gravity. We have all this obvious evidence, but the underlying stuff is kinda misty. Newton knew gravity existed and made some nice laws. Einstein said why those laws work. String theory is a more comprehensive way of explaining Einstein's theories. Science changes, because it needs to.

Re:How this impacts evolutionary theory

[filmmaker]

Science changes, because it needs to.

Right. But also, because is those changes. Science is not some dogma, it's a process. So, for anyone who wants to get snarky about "holes" in evolution, well, no pooh-pooh Sherlock. It's not about authority or control, science is, instead, a process by which we attempt to attain and refine knowledge.

Re:Sex bias in reporting?

[Anonymous Coward]

It's always possible that the other scientists involved had no comments to offer.

Don't look for conspiracy where stupidity or simplicity can solve the mystery.

Also, are you REALLY shocked that the New York Times has failed to completely and accurately reflect all of the facts in their journalism?

Re:Sex bias in reporting?

[Anonymous Coward]

Come on people. Why is it that every time there is a woman involved it automatically becomes an issue of gender discrimination????

Most scientific articles have a single author that deals with inquiries and correspondences. Look at the actual paper (Nature, 24 March 2005). The author to which correspondences should be directed is Dr. Pruitt.

Re:How this impacts evolutionary theory

[Chris Burke]

Without a backup copy, there should have been no way for the gene to revert. Yet it did, so we're left with an odd conundrum. :-)

There is a conundrum as to what the recovery mechanism is. There is no conundrum in evolutionary theory, because the parents both aquired a mutated gene and thus clearly the correction method isn't perfect.

As you are obviously aware (re: cancer) most mutations are bad. An evolved mechanism for correcting certain kinds of harmful mutations is hardly a conundrum for evolutionary theory.

Re:How this impacts evolutionary theory

[feepness]

Full blown "Cancer" only happens when these problems get out of control, and the body can no longer contain/fix them.

Furthermore, if lethal cancer occurs once you are past child-bearing age (around 30 up until recently), it isn't such a "bad thing" for the species. Once you've reproduced, evolution is done with you.

Re:Intelligent Design

[MightyMartian]

Why it so unacceptable to introduce the idea of "Intelligent Design" when everything about life is so structured and orderly?

Let's see:

1. Things aren't so structured and orderly. Look at your own body. Anybody who designed such flawed systems as knee joints and eyes with blind spots ought to be fired, if not outright charged with criminal negligence. Living organisms demonstrate the slow march of blind evolution, with functions and organs being co-opted for other purposes, and not being calibrated for ultimate efficiency. As much as anything else, organisms tend to look like compromises, and not optimal designs. They certainly don't resemble entities that we observe to be designed.

2. How could science ever pursue something like "Intelligent Design"? Who is this designer? Where did they design life? What forces did it/they bring to bear? How can a researcher hope to falsify any particular claim about the designer? These are the sorts of questions that must be answered, and in reference to evidence that can actually be gathered. That is how science functions.

Why is chance so much more believable?

This sentence betrays some substantial misunderstanding of evolutionary theory. Evolution is not pure chance. Mutations themselves are likely to be so, but the selective processes are not random.

As well, what does "believability" have to do with it at all? Science follows the evidence, not the conceits and sensibilities of people. Imagine going back in time 5,000 years and telling some Mesopotomian that Earth is a sphere that orbits the sun, which itself orbits the central mass of a vast galaxy with billions of stars, which in turn is itself only a rather ordinary member of a vast cluster of galaxies. That you cannot imagine (or refuse to imagine) something to occur is not an argument against it, but merely fallacious thinking.

Re:Sex bias in reporting?

[Xylantiel]

Right - going to meetings, writing grants and papers... i.e. commenting on the work. That's what the reporter wants. PIs generally are quick to answer questions of what's going on in their lab and why it's interesting.

Double Mutation?

[bryan8m]

Could this gene simply be more likely to mutate and it just mutates back to the normal state?

Re:How this impacts evolutionary theory

[MagicDude]

If a mechanism exists that prevents or corrects mutations across generations, then the theorists may *again* have to go back to the drawing board.

Just because there is a backup mechanism that can prevent mutations from being passed on doesn't mean it works 100% of the time.

In DNA replication, there are enzymes that scan the replicated strands specifically to make sure base pair matching occured correctly, and when it hasn't it can fix the problem. Without it, the number of DNA errors would be several orders of magnitude higher than they are. However, this doesn't always work. For example, take a common replication error is when an incorrect base pair is matched. So where a G should have been matched with a C, an error takes place where a T is matched with a C. Now, ordinarily the error-checking enzyme would notice that error and change the T back to a G, but sometimes it goofs, and fixes the wrong half of the error, so in this case it would change the C (which is the correct base) to an A (to match with the incorrect T). Thus, a mutation has occured in spite of a backup mechanism to insure genetic reproduction. Who's to say that this mechanism of genetic protection in the article can't malfunction in a similar way?

Re:How this impacts evolutionary theory

[aichpvee]

Should be noted, because a lot of the creationist kids around here don't seem to understand, that when someone says "know" or "they can tell" or "they decide" in these contexts, the poster is NOT talking about a conscious intelligence making a decision. They are making an anthropomorphization and only a moron would take it literally (as I have already seen several people do on this page.)

Re:How this impacts evolutionary theory

[Chris Burke]

It isn't clear to me how this contradicts anything we already know. It only presents a new behavior that we don't yet understand.

The plant still mutates. These mutations can exist in the plants, and be passed on to children. That is what evolutionary theory predicts/requires. That there is a newly discovered and not yet understood mechanism for repairing some mutations is fascinating, but how does it represent an error in our previous understanding? Just because we weren't aware of all ways in which the negative effects of mutation could be mitigated?

Re:How this impacts evolutionary theory

[thefirelane]

There are certain somatic (IE: not passed down from generation to generation) mutations and other varieties of DNA damage that lead to cancer. There is a mechanism in place to replace these mutations with another copy. The body also has a way of detecting and removing some viruses and retroviruses that have embedded themselves in the DNA of the host organism, to a limited extent.

This is true, but everything you describe is where the organism detects genetic changes when it has a clear copy of the 'good' genes elsewhere. In the case of cancer... one cell mutates, but all the others still have the good DNA. The thing that makes this case so interesting, from what I understand, is that the entire organism had the new DNA so what would it compare against... (no I didn't read the article yet)

never seen "cruft" in designed code?

[Anonymous Coward]

Dude - I'm not arguing for "Intelligent Design", but have you never seen so-called "cruft" in source code of years-old systems? Would you try to argue that such source code must have evolved itself through exposure to an invisible and external-to-the-source-code neural-net (i.e. dumb automaton that just keeps trying stuff until it finds things that work better than before even if sub-optimal) because any developer who wrote crap like that would have been fired after the first dozen sub-optimal changes?

Something as bad as the Windows source code could only have happened by accident, right?

Jeez ... wake up and learn to really (i.e. "critically") think instead of just parroting back what somebody told you to believe!

Re:Intelligent Design

[MightyMartian]

If you came across a sand castle on a beach is your first reaction to say that the wind and waves created it. Or do you belive that something intelligent created it?

Since I know from experience that sand castles are designed by people, when I see one on the beach, simple deductive reasoning allows me to say "That's very likely designed." In other words, your analogy is flawed, as all such watchmaker analogies are, at their very core. Beyond that, in the sciences that do deal with intelligence design (archaeology and forensics come to mind), a good deal of effort has to be put into showing that certain processes or artifacts are, in fact, the products of an intelligent designer. I personally could walk through a field strewn with Acheulian tools and not recognize them as being the product of an intelligent mind.

The more macro and micro we look at things all we find is structure and order.

I don't see this at all. The more we observe the world revealed by genetics, the more we observe the messiness of evolution, viral sequences in our genome, genes that are minimally active leading to primates like ourselves being unable to produce sufficient Vitamin C, thus requiring us to gain it in our foods. Simply waving your hands and saying "it's structured" doesn't really say anything at all, and is simply another demonstration of your fallacious thinking.

Re:How this impacts evolutionary theory

[filmmaker]

Well, I know what you're saying. However, I'd submit that the cultural climate right now is dangerous. I'd submit that those folks who subscribe to the Christian faith, a particular mythology, and a damn fine one if I may say so myself, have attained a position in America's mainstream consciousness, in its government and in its media that is dangerous. The average person is actually starting to believe his own hype, sort of like Bono did right around the time of Joshua Tree, hence all the subsequent sucky US albums. Fact is, just because media panders to the right for its own reasons (ad revenue, of course), that doesn't legitimize what are, let's face it, on the whole some pretty insane and downright dangersous beliefs and dogmatic belief systems.

No after market support from the manufacturer?

[tlambert]

Why it so unacceptable to introduce the idea of "Intelligent Design" when everything about life is so structured and orderly?

No after market support from the manufacturer?

-- Terry

The ability to evolve had to evolve

[couch_warrior]

While the religious side of me revels in the prospect that evolution may be proved impossible, the scientific side looks to the larger picture.
The Darwinian view of evolution through slow mutation was proved wrong long ago by the fossil record. This knowledge has been closely held for fear the press would get ahold of it and have a field day. But based on the fossil record, it appears that evolution only happens when small populations are isolated and run short on resources.

THERFORE - it is easy to theorize that genes have (at least) two maintenance modes programmed into them: ONE- we're thriving in a time of abundance - keep things from changing by repairng mistakes; TWO- We're dying off due to hostil conditions - quick, mutate and try to find a way to cope with this. This is why breeders can cause dogs, cats, birds, plants, to change into such bizarre forms in a few generations by breeding offspring back with parents - it simulates a dying population, and activates the evolve to escape mechanism.

This evolutionary ability must itself have had to develop by the slow route, which is why life developed so little diversity for the first few hundred million years. But then, once the evolutionary mechanism was created - it kicked in and species began springing up all over the place.IMHO anyway

Re:How this impacts evolutionary theory

[logpoacher]

One counter-argument might run that although we might be going downhill fast in evolutionary terms, we're also going uphill very fast technologically.

Doesn't matter how dumb the primordial organic neuroprocessor is when it's been augmented with a Cyberdyne Systems omni-intelligent prepare-to-be-assimilated super jewel. Or, translated into Earth-speak, in the time-frame that these problems might become manifest, we might be able to fix them, or make them irrelevant.

Now, the above argument can be fired at all sorts of things where people might prefer to sit on their asses rather than fix something - the environment, for example! - but it raises an interesting point: if you don't like the Hope-We-Can-Fix-It answer, then just what alternative solution do you propose?

We can't exactly just turn people away from hospitals; I don't think we want our government to start imposing sterilization orders on "stupid people". So the study that you propose isn't gonna result in any useful action - is it? Except that if it revealed what you suggest, it would just be used as ammunition by people who want to control everyone. And therefore, even if it's true, it isn't actually anything we want to have sanctioned!

BTW, I'm not arguing against you here - it's pretty likely, in my view, that our capabilities and societies are acting pretty anti-evolutionarily, as you say. It's debatable about how strong such influences are - the nature vs nurture debate and so on - but even assuming that the influences are strong, I'm not sure what a decent humanitarian society can do about it.

Apart from develop yet more remedial technology...

Re:How this impacts evolutionary theory

[glesga_kiss]

One counter-argument might run that although we might be going downhill fast in evolutionary terms, we're also going uphill very fast technologically.

Which IS evolution true to the word. It ain't all roses though, I can see a world ahead where everyone needs corrective eye surgery as bad eyesight genes run rampant as their damage can be undone and there is no longer any natural gene filter. The weak are flourishing and breeding, where as one hundred years ago they wouldn't have made it to childbearing age. Our reliance on technology will only become greater the more we use it.

It's a messed up issue. What can you do to prevent it? Nothing without breaking most moral and ethical taboos! We may actually be forced to start correcting genes in our children in the future should it start to get really bad. It's devolution of the species, but evolution of the society.

Nature often has a solution. Plagues and such like, though not very nice, can actually serve as a strenghener for the population as a whole. It is reckoned by many that Europe has a lower HIV infection rate due to the bubonic plagues. I believe that the study found that 25% of the population were resistant to HIV entirely.

So, we could be setting ourselves up for a big fall (and with our own bioengineering creating new viri...) but it'll likely all work out in the end.

Re:Double Mutation?

[Wabin]

That would be a possibility, but two things make it unlikely (from the actual Nature article, which I can read, being at a University with a subscription): One is that if it were just a region of high mutation, then you would expect to see other changes in the gene. They don't find them. The other thing is that they have this behavior at 11 sites in the gene. So it is not as if there is one site that is flipping around all the time. There is something strange going on. I don't really have a good sense of what it is, and the RNA backup hypothesis will be pretty easy to check. I expect there will be a lot of work on this in the next few years, and we should have some answers soon enough.

Re:Intelligent Design

[MightyMartian]

The lesson in all of this is that in the real world (and not in the demented heads of Intelligent Design "theorists") recognizing design is not a trivial matter for objects that we have not actually seen designed before. Of course one is going to know a sandcastle is constructed, because one's experience is that sandcastles are designed and built. If you have to actually deal with objects or processes where every day common experience cannot be used to compare to, then things get very tricky. Heck the first guys to spot pulsars thought the source might be LGMs, simply because of the extreme regularity of the signal. The lesson here is that regularity doesn't mean design, or, in other words, not every watch indicates a watchmaker.

But Intelligent Design isn't really about that anyways. Its essence is nothing more than "somehow something somewhere is wrong with evolution". It's simply about disguising the obvious theological aspects of Creationism behind the guise of pseudo-science. The ID advocates change their tune depending upon the audience. To critics, the Intelligent Designer could be an alien race. To the Creationists, of course, they don't try to hide the fact that the Intelligent Designer is the Biblical God. It's the fundemental deceit of the movement that it's real interest isn't furthering knowledge, but trying to force science away from following lines of evidence that they believe questions their religious beliefs.

wrong

[JeremyALogan]

"a corrected version of a defective gene inherited from both their parents"

turns out that two wrongs DO make a right