Plants May Be Able To Correct Mutated Genes 363
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.'"
How this impacts evolutionary theory (Score:5, Interesting)
Isn't it amazing how the more we know, the less we know?
Re:How this impacts evolutionary theory (Score:3, Interesting)
Re:How this impacts evolutionary theory (Score:4, Interesting)
Sex bias in reporting? (Score:3, Interesting)
Re:How this impacts evolutionary theory (Score:5, Interesting)
Cancer is caused by a DNA mutation that your body failed to correct. Errors are extremely common. The only reason why we survive is our body's repair mechanism. In the case of these plants, neither parent had a correct gene. 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.
That's not to say that the theories behind mutations are all wrong, but we could be seeing something akin to problems with Newtonian physics.
Re:How this impacts evolutionary theory (Score:5, Interesting)
Maybe it's the result of mutation (Score:2, Interesting)
I'm pretty close to this research... (Score:5, Interesting)
This really is no joke, these results are really exciting! I suggest everyone read the article.
All information not in yet (Score:3, Interesting)
Re:I'm pretty close to this research... (Score:3, Interesting)
Never the less, this is not the death-knell of evolution, or in any way contradictory to it, though I know kook organizations like Answers in Genesis and the Discovery Institute will lie their heads off to make it look that way.
Plants have huge genomes (Score:3, Interesting)
I haven't bothered to register to read the article, so maybe this is discussed already: I have been told that plants (or at least some of them) have a lot of DNA due to, among other things, spurious repetitions of partial sequences. I don't have any numbers for nucleic DNA, but I think I saw somewhere examples of plants having more than 100,000 base pairs of mitochondrial DNA, compared to some 16,500 for humans. I guess those repetitions might work as a backup, and help revert an earlier mutation.
I'm not a geneticist by profession though, so what I'm telling here may be an urban legend...
Backup Copies Exist for Many Genes (Score:5, Interesting)
Re:Intelligent Design (Score:0, Interesting)
Why plants have complex genomes (Score:3, Interesting)
Exactly, and there's a reason for that crazy complexity. The core challenge for a plant is that it cannot move. It has to handle all the processes of life whilst living where ever it happened to sprout. If the sunlight is intense or shaded; if the ground is wet or dry; if a caterpillar munches on the plant; if the soil is laced with silicon or deficient in phosphorus; or whatever, the plant can't do much about it but activate/deactivate genes. As a result, they have evolved a more complex genome with a greater number of IF-THEN or CASE statements built-in.
In contrast, most animals are nicely mobile, if they don't like their environment, they move to a better location. As such animals don't need as complex a genome because they spend most of their lives in their chosen micro-climate.
Re:How this impacts evolutionary theory (Score:1, Interesting)
Re:Intelligent Design (Score:4, Interesting)
When you see Mt. Rushmore you think of a creator, I suppose, but when you see a rock outcropping ade to look like a face by weathering you also might think of a creator. In the second case you'd be wrong.
Re:Backup Copies Exist for Many Genes (Score:2, Interesting)
We also frequently find that single genes are duplicated by themselves, or that entire segments of a chromosome may be duplicated by the process of 'segmental duplication'. The interesting thing here is that the scientist believe that a second copy of the gene does not exist as a DNA copy, but as an RNA copy.
Order of credit (Score:5, Interesting)
(1) Who got the grant
(2) Who has the most tenure
(3) Who went to the meetings
(4) Who wrote the paper
(5) Whoever is politically in and most needs a paper credit to keep on tenure track
(6) etc.
Actually doing work tends to come dead last. Sometimes (as some recent scandals have shown), it doesn't come at all.
Also, realize that to a scientist, it's not about the credit for getting something done, it's about the fact that it needed to be done, and someone did it.
For every scientist popularized by the media, there are thousands of them of whom almost nobody has ever heard, but who were critically important for fundamental things we take for granted every day.
For example, some of the first posts in this thread were going on about retrying the Scopes "Monkey Trial" vs. Darwinian evolution, when most biologists today know that the currently accepted evolutionary theory is Jerry Pounelle's "Punctuated Equilibria", and Darwin is generally only taught for having come up with, and written about, the idea of change in species over time.
-- Terry
Re:Planet RAID. (Score:3, Interesting)
Of course I don't remember too much about sexual plant reproduction - for all I know plants don't have animal-type tRNA...somebody will correct me I'm sure.
So what? Consider your sand castle (Score:1, Interesting)
Until you got very micro--then you'd see crystal structure and atomic order *as described by science.* Or until you got very macro--then you'd see astronomical structure and order *as described by science.*
Science goes beyond the mere recognition of structure and order, to read, understand, and predict, at a detailed level, what exactly the structure and order is.
Not only is order and structure expected according to our most current scientific understanding of the world and universe, it conforms very closely to the scientific theories we have formulate to describe the structure and order.
Besides, structure and order in and of themselves mean nothing to your argument. You're ASSUMING that structure and order can only arise from intelligence. To apply your way of thinking, what you would need to prove is that such structure and order could *only* arise through intelligent design. Good luck with that one.
Re:No, not really (Score:2, Interesting)
If the mutation is not too severe and/or there arent multiple mutations
AND
The plant is good at math (ok, the plant chromosonal equivalant)
THEN it can generate a new copy of the old version when it reproduces.
I am probably missing a second AND something to get it down to 5%.
They didnt see an obvious Dup but we certainly don't know the plant chromosonal equivalent logarithems! ((or they hired the slashdot editors to look for the dup copy...))
Re:How this impacts evolutionary theory (Score:2, Interesting)
It's been over 20 years since my last biology class (well, not counting some recent anatomy & physiology in massage school) so this might be a dumb idea; but I wonder if there could be some sort of "parity bits" in the "junk" DNA? Not a full backup copy, but enough extra information to be able to correct some mistakes.
Re:The ability to evolve had to evolve (Score:2, Interesting)
The reason domestic dogs, cats etc. can be distorted rapidly is by replacing the natural selection by human intervention and selecting for another goal.
Species form by separation of breeding populations when geographical boundaries are formed not by some weird slow/fast switch.
Re:Why does it happen so seldom? (Score:2, Interesting)
Speculating wildly, I suspect it could be more an "accident" than correction mechanism--the correct sequence may be in some RNA reservoir which occasionally gets "mistakenly" inserted in the normal reproduction process. We never noticed before, because normally the RNA sequence would complement the DNA sequence completely. But even this would be amazing, since we don't know how or when that would happen.
I can't quite figure out when this would be especially useful as a corrective mechanism; if it were actually triggered to come into play correct non-adaptive mutations a generation later, it would be mind-bogglingly huge as a discovery.
A third possibility is, of course, a misleading experimental result. That would still be interesting, but only because it made the cover of Nature
Re:So what happens to gentically modified plants? (Score:2, Interesting)
In bacterial cultures, it was fairly straightforward to select for resistance to a given antibiotic.
You put a bit of antibiotic into the agar, and the colonies that survive got transferred to an agar with a higher concentration of the antibiotic. And so on, until either a level was reached where none of the strains would grow, or they were completely resitant. Pretty cool stuff
By this stage, we had usually got a strain totally resistant. Then came the interesting bit.
We took the antibiotic out of the growth media, and grew several more generations. It took us quite a while, from memory, we spent a whole term working on this experiment.
At the end, we took those colonies, and put them back on several different strengths of the antibiotic. The vast majority of the colonies had lost their resistance - without a force in the environment to select for it, it was lost from teh population.
The same thing will happen for genetically engineered species, (eg roundup resistance) If there's no force in the environment to select for it, then the genes will disappear.
Re:So what happens to gentically modified plants? (Score:3, Interesting)
If you keep constant pressure on them, you'll kill all non-resistant plants from the field. It's like with bacteria. As long as you keep ampicillian in the dish, they'll keep their resistance. If you stop challenging them, they'll start to lose their resistance.
If that crop got out in the wild, though, it wouldn't last long at all. Most wild plants don't get sprayed with herbicides, so they'll be wasting energy. A pesticide producing crop very well could retain their special trait in the wild. Many plant already do produce pesticides.
The reason that farmers are forbidden from using their own crop for seed isn't genetic, it's corporate. If they did use their own seed, they effectively become a competitor with the people they bought the seed from to begin with. If your customer can make the same thing you do, they'll always undersell it to themselves.