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Half-Life of DNA is 521 Years, Jurassic Park Impossible After All
another random user writes with this quote from Nature News:
"Few researchers have given credence to claims that samples of dinosaur DNA have survived to the present day, but no one knew just how long it would take for genetic material to fall apart. Now, a study of fossils found in New Zealand is laying the matter to rest — and putting paid to hopes of cloning a Tyrannosaurus rex (abstract). After cell death, enzymes start to break down the bonds between the nucleotides that form the backbone of DNA, and micro-organisms speed the decay. In the long run, however, reactions with water are thought to be responsible for most bond degradation. Groundwater is almost ubiquitous, so DNA in buried bone samples should, in theory, degrade at a set rate. Determining that rate has been difficult because it is rare to find large sets of DNA-containing fossils with which to make meaningful comparisons. To make matters worse, variable environmental conditions such as temperature, degree of microbial attack and oxygenation alter the speed of the decay process. By comparing the specimens' ages and degrees of DNA degradation, the researchers calculated that DNA has a half-life of 521 years. That means that after 521 years, half of the bonds between nucleotides in the backbone of a sample would have broken; after another 521 years half of the remaining bonds would have gone; and so on."
Russian and Korean Researchers Will Inject Mammoth DNA Into Elephant Eggs, Resurrecting 10,000-Year-Old Beast
A mosquito that bit a dinosaur encased in amber....
Quick, what does this mean regarding mammoth burgers?
"Putting paid"? WTF does that mean?
You're telling me no manner of preservation could get us T-Rex dna? And we've got nearly complete mammoths, furry hides and all, in giant blocks of ice, but no DNA?
Something about this don't seem right. I want to speak with Dr. Alan Grant.
Nobody has scientifically disproved time travel yet... we may yet get to see dinosaurs alive!
Does this have any bearing on cryogenics or would that preserve the DNA?
...for God's sake, lets get samples and clone Keith Richards before its too late!?!?!?
Light travels faster than sound. This is why some people appear bright until you hear them speak.........
Yes, water and stuff is bad for DNA, m'kay? Didn't they know that is why you use blood of dinosaurs that is enclosed in amber? D'uh.
Just do not fix the holes was DNA from frogs. That's going to end badly...
Jurassic Park had it figured out. They patched the destroyed parts with frogs DNA which fucked up everything
So in amber, or some other similar impermeable substance, the chemical reactions requiring water or air might well be prevented or dramatically slowed, thus the degradation of DNA might be substantially slower than the 521 years described in the summary.
Not necessarily the end of the Jurassic Park idea.
If the Government becomes a lawbreaker, it breeds contempt for law;
the old fashioned way.
Ba-dum-cha!
-badford
Just use frog dna to fill in the holes...nothing could possibli go wrong.
If the half-life of DNA is 521 years how are scientists able to sequence 30.000 year old Neanderthal DNA? Presumably this applies to regular DNA, did Svante Pääbo and his team sequence mtDNA?
Only to idiots, are orders laws.
-- Henning von Tresckow
Perl Programmer for hire
What about the 30,000 year old seed that sprouted? http://www.popsci.com/science/article/2012-02/russian-scientists-resurrect-pleistocene-era-plants-buried-siberian-permafrost-30000-years
It was based off DNA from blood from an insect trapped in amber.
Now, the enzyme degradation will no doubt be an issue, as well as the rareness of mosquitoes preserved in amber, but that's another matter.
What if it is sealed in a way that microbes, oxygen, etc can not interfere with it? Say amber, a tar swamp, a deep freeze?
No I did not read the article nor do I have any knowledge on the subject beyond that leaving a steak on a counter in 100 degree heat has a very different outcome than putting it in a sealed bag in a freezer.
can't sleep slashdot will eat me
So, it's been about 65,000,000 years since the dinosaurs became extinct. Which means each piece of DNA has degraded by half 130,000 times. 1/2^130,000 is about 1 e -39000. Which is a lot of zeros. Each recovered strand conveys an infinitismal amount of information about the original. If you had only one cell, you could barely guess at the original DNA sequence.
But that doesn't make it impossible. Because all the cells of a given organism are genetically identical (or close enough) when the animal died. With enough cells, you can theoretically "average out" the (presumed random) noise until the underlying "signal" of the original DNA sequence emerges. It will take a LOT of samples, but organisms have a LOT of cells.
Wikipedia seems to have a page all about doing what this article says is impossible: http://en.wikipedia.org/wiki/Ancient_DNA
It claims there are multiple cases of Neanderthal DNA being sequenced, and a couple quick google searches seem to indicate there are many other similar situations where DNA was recovered.
So i'm wondering, did this study perhaps prove that if nothing is done to preserve the DNA after death then... surprise! The DNA isn't preserved?
This Space Intentionally Left Blank
The 521 year half-life is if the DNA is exposed to water in typical situations, ITFA (in the article) they give an estimate for the best case situation...
The team predicts that even in a bone at an ideal preservation temperature of 5 C, effectively every bond would be destroyed after a maximum of 6.8 million years. The DNA would cease to be readable much earlier — perhaps after roughly 1.5 million years, when the remaining strands would be too short to give meaningful information.
“This confirms the widely held suspicion that claims of DNA from dinosaurs and ancient insects trapped in amber are incorrect,” says Simon Ho, a computational evolutionary biologist at the University of Sydney in Australia. However, although 6.8 million years is nowhere near the age of a dinosaur bone — which would be at least 65 million years old — “We might be able to break the record for the oldest authentic DNA sequence, which currently stands at about half a million years,” says Ho.
As other posters point out, the famous mammoth recreated from DNA was from about 10,000 years ago, much less than the 1.5 million year practical limit estimated by this research team.
If ape and human DNA are 5-10% different, then perhaps dinosaur and some current reptile DNA are very similar as well, since now you have 90% of the DNA already, you have to find much less, and if you have billions of samples of DNA, perhaps they could be reconstructed. I would think that by the time we are able to do such a thing we won't be far from being able to create our own dinosaur from scratch.
Okay, but there were how many billion copies of the sample when the creature died? If there were two, after 521 years I still have (on average) at least one copy of 3/4 of the data, extending the half-life to (check my math here) 737 years. With 15 billion copies or so, the half-life gets up to, hey!, about 65 million years, and there are trillions of cells (and so trillions of copies of DNA) in a human-sized body.
Those who fail to understand communication protocols, are doomed to repeat them over port 80.
It's not impossible. You just show the computer a photo of a dinosaur, let it start from the DNA of a Komodo Dragon, and let it try different "what if" changes to the DNA, simulating the growth of the each resulting organism. Could even happen within the lifetime of Randall Munroe.
Just get more of it. Problem solved.
With the transport of water into and out of a bone - how old are those bones now?
> ... a photo of a dinosaur ...
I think you have a bit of a problem in step 1
Is this why we haven't heard much from Mary Schwietzer lately? Six years ago she isolated soft tissue remnants from inside a T-rex femur.
More recently, Charlotte Oskam (Biologist at Murdoch University in Australia) identified DNA in fossilized egg shells.
We've always known that DNA was unlikely to survive the passage of aeons, this just puts a number to it. Specific conditions could still allow better than typical preservation, and so I dislike making an absolute statement that we'll never find it. Hopefully those who are still looking for the elusive ancient DNA will take this study as a way to focus their search rather than have their funding cut.
"Space Exploration is not endless circles in low earth orbit." -Buzz Aldrin
But we're going to explain to you how half-lives work anyways.
moox. for a new generation.
I wonder if 521 years is how long we'll be waiting for Half Life 3?
Welcome to Dodo Park.
Sorry, it just doesn't have the same ring to it.
Any insufficiently advanced magic is indistinguishable from technology.
This doesn't fundamentally change anything. Even if half your DNA is destroyed every 521 years, large multicellular organisms have trillions of cells containing copies of their DNA. You don't need to find a single complete correct set. That is already hard enough to do in living organisms. You can assemble a mostly complete set from many incomplete sets. Recovering data from a harddrive with corrupted data is very hard. Recovering the data from a trillion copies of the same data that was corrupted in different random ways is much much easier. As long as every section of data survived in some of the copies, it can be reassembled. Even if there is not enough DNA in a single organism to do this, the differences between the DNA of individuals of the same species is very small. This is what makes sexual reproduction possible. Maybe we can't clone a T-Rex, but if we find enough genetically similar DNA from multiple T-Rexs, we can theoretically make a T-Rex "offspring" of all of them. We don't really care about cloning an specific individual T-Rex anyway. A genetic T-Rex that never existed, but does now, is perfectly acceptable. Maybe there isn't enough T-Rex DNA in the whole world to make a coherent set of DNA. That's possible. All I am saying is that we still have some more good tricks up our sleeve, and we shouldn't give up yet. We will certainly clone some kind of Pleistocene organism like a mammoth as an earlier step anyway. No reason to decide what are limits are so early in the game.
Even given the half life, we may be able to resurrect dinosaurs. Remember that we are talking about information that is encoded, with billions of copies hanging around. Given we can find enough samples, even if they are all missing different portions, we may be able to piece together the complete sequence by combining the portions of each sample that survived. Throw in extremely cold temperatures like the article talks about, and some Jurassic-park style replacement of certain portions from modern animals, and it is still very possible. Maybe not today, but in 100 years I can see it being very possible.
Just because I can hook a shark from a boat, I do no offer to wrestle it in the water.
How does roadkill taste?
(And no, I don't know how mammoth tastes either).
"Kill 'em all and let Root sort 'em out"
...or so researchers claimed. I know there was some skepticism around their claim, but was it ever refuted?
Since each cell's DNA is essentially a duplicate of all others, is it possible to compensate over this short half life by using millions of cells from the same creature with error correction in order to reconstruct the original sequence correctly in its entirety?
One of the best ways to make it happen is to declare it's "impossible". It gives people something to strive for.
For those who don't know, in 2005 it was announced a paleontologist had inadvertently found what appeared to be remnants of blood and or related items inside a t. Rex fossil. Three reference stories:
Story 1
Storey 2
Story 3
IF, and that's a big if, what this paleontologist has found is un-fossilized bits of t. Rex, would it be possible to see if any bits of DNA remain? As she states in the third article, she is not equipped to look for DNA and so can't do it.
Not doubting what the research has found, but if this stuff is something that is real, would it hurt to look and prove the exception to the rule?
We will bankrupt ourselves in the vain search for absolute security. -- Dwight D. Eisenhower
Comment removed based on user account deletion
Yet this was possible...
---------
Amplification and sequencing of DNA from a 120-135-million-year-old weevil.
http://www.ncbi.nlm.nih.gov/pubmed/8505978
This ignores the ability to do statistical analysis of the breakdown products, and the ability to build the DNA from the analysis. It may be impossible to use the DNA, but that does not mean it is impossible to rebuild it.
521 years is well within the range of the dodo. Time to get started scientists.
Surely with a large enough sample & the fact that most organisms share the vast majority of DNA make-up you'd be able to piece together an accurate picture of dinosaur DNA in-spite of half life degradation?
I mean, it's not going to be linear in the way that half the data would be lost forever so if you have many samples, you'd surely be able to find some parts of the sequence which could fill the gaps where other parts are lost.
...since the world is only about 6000 years old!
What if we just bookmark the DNA under our Coding sub-directory that is synced to The Cloud?
Surely that should save it?
Since dinosaurs went extinct just 6000 years ago, it shouldn't be all that hard to find some DNA that's not too terribly degraded.
My house is built on layers of rock containing some amazingly well preserved ~400M year old fossils, and there appears to be very little water because the iron in the clay is not rusted, making it bright blue instead of brown. It is brown however where the rocks have been cracked and water can get through.
Maybe Neanderthals are not that old.... The better question, is how do we have dinosaurs with red blood cells? If DNA can barely survive for 500+ years, and cannot survive more than 1.5 million, how do red blood cells last 65 million years since the presumed extinction impact event?
Creationists will be VERY interested in this article.
Peter predicted that you would "deliberately forget" creation 2000 years ago...
What about those?
So this means we're gonna need more frogs to juice?
What this says is that after many years many DNS bonds have been broken and so that DNA is not viable.
What it does NOT say is that after many years we can not use that broken DNA to figure out what the DNA sequence must have been when it was alive. Genetics is close to the point where, given damaged DNA, we can figure out what the original sequence was, and artificially construct DNA with that sequence using other material.The damaged T-Rex DNA will tell us what the original T-Rex DNA was, and we will be able to build our own clone from raw chemicals.
Really?
IANAScientist but Egypt has spent years DNA testing mummies to identify suspected remains of family dynasties. Most of these are several thousand of years old. By the logic of the article there should be less than 6% of the DNA remaining in a 2000 year old mummy. Yet time after time they have been able to identify remains that have markers clearly indicating they are related.
Cut and Paste error
Given this half-life of 521 years for DNA preserved in fossils, I have to wonder about the half-life of DNA in living things. Specifically in us. Based on that figure, after 40 years, a little over 5% of the DNA in anything would have self-destructed. Although it turns out that we do, after all, grow new cells in our brains, some of our cells, such as the really, really long ones in our spinal cords are there for life, are pretty vital, and are not replaced. If the DNA in those cells spontaneously destroys itself, then they die. So, the question I have is, how many of them can we lose before we're paralyzed. Also, the 521 years seems to be some sort of averaged upper limit. The kinds of conditions they suggest will destroy the DNA are far, far more common in the human body, so being in a living human body should push that half-life way way down. By the reasoning they're using in this story, it seems like a human body would necessarily have to stop functioning within a timeframe much shorter than an average lifespan.
Now, I think it probably is pretty unlikely that dinosaur DNA could last until modern times. But I've seen enough of these back of an envelope calculations by people with some sort of axe to grind against some pet peeve of theirs. In this case, the pet peeve being the idea that DNA could survive tens of millions of years. Lots of ridiculous ideas about living things, especially about dinosaurs, have been "proven" this way in the past. The proofs never seem to hold up to actual real-world evidence. One of my favorites is a double-whammy. It was once "proven" that large sauropods couldn't have spent their lives walking around on the bottom of lakes and swamps with their heads held up to the surface to breath because the pressure at those depths would have crushed their throats. It sounds like a pretty good theory when you apply a pressure of about one extra atmosphere to something like a garden hose. When you apply it to a sauropods neck, which is a construction of bone and cartilage and muscle, thicker at the base than a human is tall, it's clearly ridiculous. If they were adapted to live walking around on the bottom of bodies of water, the throats of sauropods would have been able to suck air down against the pressure. The double whammy part is that the theory that useless "proof" was disproving was itself based on a similar ridiculous "proof". The theory in question was that large sauropods had to spend their lives in water because their legs clearly couldn't have taken the strain. The problem is, the assumptions that went into that "proof" also would have disallowed all kinds of other large animals, including other large dinosaurs who clearly didn't live in water and probably modern elephants as well. So, it was one ridiculous proof to disprove another.
Similar logic has disproven all sorts of things, such as kangaroos and sturgeon (which have both been calculated to not exist because they supposedly did not consume enough food to provide all the energy they use). Bees and other insects have been proven incapable of flying, etc. I remember an example in a math magazine in school when I was very young which explained that dragons couldn't fly because their wings couldn't generate enough downward thrust to counter their weight. Quite aside from the large number of assumptions needed to actually get any figures for imaginary animals, the article completely ignored the fact that there's almost nothing in nature that flies by directly countering its weight with downward thrust. It also ignored the existence of winged flying machines in excess of 300 tons.
So, I take anything like this with a huge grain of salt. It very probably is the case that dinosaur DNA hasn't been preserved (except in their descendants), but the "proof" is a pointless mathematical game. They might as well be counting the letters in bible verses to find hidden codes.
But if millions of cells are analyzed, won't they each have different parts of the chain degraded (or more to the point, intact)? Looking at patterns of surviving snippets, couldn't we conceivably put together a complete chain, given enough samples?
The perfect combination! When will it be up on Steam?
Tubal-Cain smokes the white owl.
The mammoth caracas they excavated was buried in permafrost, so these half-life numbers would not apply.
As Jack Horner discusses in this TED Talk:
http://youtube.com/watch?v=0QVXdEOiCw8
- "Scientia non habet inimicum nisp ignorantem"
The stability of DNA embedded in amber was not measured, which was the entire premise of Jurassic Park. Therefore, the authors' dismissal of DNA embedded in amber as being sufficiently stable to support a "Jurassic Park" scenario is complete and utter speculation, not science. This all seems like a coordinated plan between authors and publisher (Nature) to get attention.
I'm not sure that the summary's defintion of half-life is correct. It says that after 521 years, half of the bonds would be gone. If you took out half of the bonds, all you'd have is pairs of nucleotides, which would mean all of the DNA is basically destroyed as far as genetic sequences are concerned. Typically, half-life means "the time after which half remains."
So if applied in the sense, I'd expect half-life to mean "the time after which half of the DNA is properly intact." In other words, after 521 years, on average, all of your chromosomes would be broken in half.
But that doesn't seem right either. I'd expect it to decay must faster.
So, if DNA has such a hard time traveling in time, how about in the interplanetary/interstellar environment, where UV and radiation exposure can be pretty bad?
I mean, if DNA can't survive on earth, for very long, could viable organisms realistically transit from planet to planet or star system to star system by natural means?
In the past, I've argued that exposure to radiation would eventually degrade to randomness any complex organic molecule in the harsh environment of space. The only shot that something organic traveling at any reasonable speed could get from star to star or even from planet to planet would be either to be massively shielded, or to be metabolically active and continually repairing damage. Also, that "eventually" was a far smaller timescale than, say, star system to star system, or even most likely interplanetary trajectories. And then there's the re-entry problem....
Was I right?
--PM
What I'm saying. A few years ago there were researchers cracking open fossils to reveal soft tissue.
The summary could actually be correct, but it shouts (perhaps incorrectly) "I am stupid!" Why not include the obviously-needed missing thought?
As copyright owner of this comment, I authorize everyone to defeat any technological measure which limits access to it.
After all, since the earth is only 9000 years old, and Jesus rode dinosaurs, we just have to get DNA from those and then ask an Angel to transmogrify it back into usable DNA.
Right?
(actually, extreme cold is why we have mammoth DNA and may result in dinosaur DNA, I'm just arguing the Moron Viewpoint)
-- Tigger warning: This post may contain tiggers! --
Shouldn't this be testable. There are plenty of corpses from 521 hundred years ago. Get DNA from something 521 years old. Check how many bonds are broken.
Life, will find a way
- Jeff Goldblum
the assumptions in the 521 year half life number is that we are above freezing temperatures. so mammoth DNA has a different experience
there are arguments to make that frozen water would lengthen the half life (frozen water is not as chemically active) or shorten it (ice crystals shredding the dna physically rather than chemically)
i'm not knowledgeable enough to guess if the frozen effect would save the DNA better or shred it even worse, but i think it is a valid to say that the half life would be a lot different if you are dealing with a corpse that was frozen at death and stayed that way in permafrost the entire thousands of years time before getting to a modern biotech lab
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
Great Auk
http://en.wikipedia.org/wiki/Great_auk
Dodo
http://en.wikipedia.org/wiki/Dodo
Baiji
http://en.wikipedia.org/wiki/Baiji
Caribbean Monk Seal
http://en.wikipedia.org/wiki/Caribbean_monk_seal
etc., etc.
And my favorite, I really want to see these:
Stellar's Sea Cow
http://en.wikipedia.org/wiki/Steller's_sea_cow
Come On Science!
I want my whale shark sized arctic manatees!
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
...the sample was encased in tree sap at death and it turned into amber? Would that preserve the DNA?
The pursuit of absolute tolerance leads to the most rigorous and ludicrous intolerance. - REX MURPHY
521 - a guess.
http://singularityhub.com/2012/03/20/raising-the-mammoth-%E2%80%93-russian-and-korean-scientists-set-out-to-bring-back-the-extinct-giant/
They seem to think DNA is viable in the samples from Russia are good for more than 400,000 years.
I think that biological material will be reconstructable and this 521 years thing is a made up number. It has to do with the initial conditions and how the sample is preserved.
In 2005 Haak et al. sequenced the DNA of 7500yo farmers from a grave in Derenburg, Germany.
So ths 521 thing - not sure what the point is.
Legalize the constitution. Think for yourself question authority.
I imagine if you inject the original "Half-Life's" code into a system 521 years from now, people will stare in awe and perplexity as a crowbar emerges from the > and bashes their heads in.
For conscience is the wound, and there's naught to staunch it
Life always finds a way...
Neanderthal DNA? Didn't somebody do somthing with their DNA?
Huh? Am I missing somthing? 50,000 years and it's still readable?
I killed da wabbit -Elmer Fudd
The paper was about a test. They tested bones of moas (a recently extinct flightless bird from NZ) that were between 600 and 8000 years old. http://www.newscientist.com/article/mg21628864.600-dnas-halflife-identified-using-fossil-bones.html
Part of the reason a DNA half-life has been so elusive is that it is hard to find a large enough cache of samples that have been exposed to similar conditions. The moa bones were all between 600 and 8000 years old, and came from a 5-kilometre-wide area of New Zealand's South Island, key factors for the researchers to identify a regular pattern of decay.
With an estimated burial temperature of 13 ÂC, the DNA's half-life was 521 years - almost 400 times longer than expected from lab experiments at similar temperatures.
The conclusion is not just that some bonds decayed in 521 years, but the data over the time frame sorta fit an exponental decay model (R2 = 0.39) from which you can say there is such a thing as a half-life (as opposed to some other decay process). For those not versed in statistics, that R2 isn't great fit, but somewhat speculative (1.0 is perfect fit, 0.5 sorta means about 1/2 of the variation can be explained by exponential decay).
For completeness, they also only measured mitochondrial DNA decay (aparently 242 base pairs), and extrapolated from other studies that nuclear DNA degrades twice as fast as mtDNA. mtDNA used for this because there are generally many more copies per cell (each cell can have several mitochondria, but only 1 nucleus). Also, it would be impractical to extract from chromosomes and measure all the bonds that broke in a nuclear DNA sample with current technology.
It was reported over a decade ago that somebody revived 250M year old bacteria.
http://www.scientificamerican.com/article.cfm?id=reviving-ancient-bacteria
If a sample is dessicated, it sounds like the 521Y half life goes out the window.
"That means that after 521 years, half of the bonds between nucleotides in the backbone of a sample would have broken; after another 521 years half of the remaining bonds would have gone; and so on." Surely you realize that this means that there would be at least one perfect set of DNA close to forever, right?
Only God can create new dinosaurs.
employ one grossly overweight hacker.
A good question!
The reverse half-life of Half Life games is 521 years: After 521 years, half of Half Life 3 will be complete.
Therefore, much like shooting a tortoise at a tree, Half Life 3 will never be finished.
Totally possible. You know which is which... from libraries and centralized, open sequence publication. Still dangerous areas to make public for manipulation, if you ask me.
There's algos for such things:
http://tech.slashdot.org/story/11/12/02/2334236/san-francisco-team-wins-darpas-de-shredding-contest
Then how did Germans at Max Planck Institute sequence the genome of Neanderthals, who disappeared 30,000 years ago?
With time travel, jurassic parc can become reality. I already created a kickstarter project.
The reason I won't read the original material is this.
Three-digits precision, after this long explanation that it all depends on so many immensely variable environmental features, from water to bacteria.
I didn't ask for an error bar, no, but just some rounding that makes sense.
Three digits here MEANS they are just not serious.
Herve S.
Since we can indefinitely keep dividing by two, there will always be an amount of viable DNA left!
When a noted scientist says something is possible, he is most likely right.
But when he says something is IMPOSSIBLE, he is most likely WRONG.
Paraphrased--but prophetic in WAY too many cases to dismiss.
Russian scientists just successfully grew flowers from seeds that were 32,000 years old. Explain that!
Synchronizing stop lights across the US = one less nuclear power plant
I think I saw that in a movie somewhere...
So , it means that we have gotted Mummie's DNA are wrong?
New study says that DNA half like is only 521year..
It means that all done study regarding ancient genetic material are wrong...Becoz it's backbone is not proper!!!
Wow....Good!!!!!