Posted on 06/04/2005 3:56:12 AM PDT by planetesimal
Scientists have extracted and decoded the DNA of a cave bear that died 40,000 years ago.
They plan to unravel the DNA of other extinct species, including our closest ancient relatives, the Neanderthals.
But they say the idea of obtaining DNA from dinosaurs, depicted in the film Jurassic Park, remains science fiction.
It is highly unlikely that viable genetic material will ever be recovered from fossils that are hundreds of millions of years old.
But the scientists hope to be able to sequence the DNA of ancient humans, which lived at the same time as cave bears, raising the prospect of perhaps one day being able to "build" a Neanderthal from their genetic blueprint.
Jurassic Park
"In hundreds or thousands of years from now, we may have advanced our technology so we can create creatures from DNA sequence information," Dr Eddy Rubin, director of the US Department of Energy Joint Genome Institute in Walnut Creek, California, told the BBC News website.
Eddy Rubin: 'We were looking for the proverbial needle in the haystack'
"I don't think we can extract DNA from dinosaurs, I think they are too old. As for creating Jurassic Park, I think that remains science fiction."
The scientists extracted DNA from the fossilised tooth and bones of cave bears found at two sites in Austria.
The cave bear was once common in Europe but died out about 10,000 years ago, when the forests shrank at the end of the Ice Age.
Dr Rubin's team analysed the extinct bear's DNA using powerful computing technology developed during the human genome project.
This approach has been hampered in the past by the fact that ancient DNA is contaminated with genetic material from bacteria and people who have handled the fossil.
Sifting out the ancient DNA from this genetic soup is like looking for a needle in a haystack.
DNA was extracted from a tooth
But because we now know the genetic sequences of many organisms - including numerous microbes, the human, and animals such as the dog - the researchers were able to "fish out" the sequences they were interested in.
In the case of the cave bear, they used the sequence of the dog, which exists in public databases, and the DNA of modern bears, as a "magnet".
Dr Rubin said it served as a "proof of principle" that the method works.
They are now turning their attention to the Neanderthals, the closest ancient relatives of modern humans, who lived around the same time as bears.
"I think it will work," he said. "It is just a matter of time."
Mitochondrial DNA
Until now it has not been possible to obtain more than fragments of DNA from animals that died out tens of thousands of years ago.
It has been very difficult thus far to get anything other than mitochondrial DNA from ancient material
Dr Dan Bradley
Most samples of ancient DNA recovered have been from mitochondria, the structures in the cell that produce energy and have their own genetic material.
While this can provide valuable information about the evolutionary history of a species, it is the DNA within the nucleus, the nuclear or genomic DNA, that contains the bulk of an animal's genetic information, including the secrets of how modern animals differ from their ancestors.
Dr Dan Bradley, an expert on ancient DNA at Trinity College, Dublin, said the research was "very encouraging".
"It has been very difficult thus far to get anything other than mitochondrial DNA from ancient material," he said.
"That is only a very small part of our DNA with limited interest."
The research is reported in the journal Science.
why not the mastadon? - frozen examples exist
Sigh. As well as being a good read, Michael Crichton's Jurassic Park has a message. It is: Don't do this. Even if you can, don't do this.
God knows what kind of monsters they'll accidentally create. The truly scary ones are probably microscopic and could spread like wildfire killings millions before a means to combat it is figured out. I mean, maybe we'll find out why the Neanderthals went extinct, and maybe we won't like the answer.
I won’t mind if they bring back Ursus Spelaeus, but please leave the Arctodus Simus DNA alone.
Perhaps someday, God willing,advanced DNA sequencing will allow us to rebuild Michael Jackson's nose.
Didn't they just find soft tissue in a dinosaur bone?
"Arctodus Simus"
Man, why are people so stingy with graphics sizes?
I couldn't find a single representation that was large enough for me to see well.
Could cloned Neanderthals vote in US elections? Paging Dr. Dean...
Or not.
When will our culture ever get over the 1950's scifi B-movie paranoia?
Prehistoric Europeans seemed to think it was dangerous to say the name for "bear" so they used euphemisms. In English and other Germanic languages the word "bear" originally meant "the brown one," and in the Slavic languages the word for bear meant "the honey eater."
GULP! A Brown-noser! wakka wakka!
Man, why are people so stingy with graphics sizes?
What about from the soft tissue recently removed from a T-Rex?
Wooly Mammoths have already been sequenced. In fact, they have been compared to both the Indian and the African elephants gene sequences to determine the "relatedness" of the WM to today's two elephant species.
Care to make a guess as to which is closer to the Mammoth?
jas3
http://www.cecalc.ula.ve/bioinformatica/oso/Arctodus_simus.jpg
Frankly, I think the work these guys are doing is in-gene-uous, and will help fossil-itate our understanding of our fore-bears. Perhaps they can even give us some insight as to our puncestors. The work they are doing now may be somewhat rudimentary, but it's almost certain to evolve.
" perhaps one day being able to "build" a Neanderthal from their genetic blueprint."
don't bother. I already know a few, and they aren't worth duplicating.
I go with the old wisdom that says we can't have archaic and breed it, too.
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