I was listening to Public Radio on the way home from work this morning. They had the Harvard professor as a guest discussing the "soft tissue DNA" recovered from a fossil that is 88 million years old. They used a technique called "bone dissolving" to find the soft tissue. Because of the limited data base using animals that are alive today, the team had to postulate several avenues to get a "match". It was a cross between reptiles and birds. I have not seen the published paper but I understand the scientific community view the results with much skeptisim and doubt. Some even calling it a "joke". Any thoughts? I am very interested to hear from some biologists what their opionions of this discovery. I had read about bone dissolving a year or two back.

seriously, if DNA can last 65 million years, then maybe the earth is only 6 K y.o., something is out of whack

Any thoughts? I am very interested to hear from some biologists what their opionions of this discovery. I had read about bone dissolving a year or two back.


It’s hard to comment without any specific links or info. Here is an interesting Q&A in which dissolving fossil bones is mentioned a few times.

http://www.pbs.org/wgbh/nova/sciencenow/3411/01-ask.html

The paper I read was that they used antibodies to Chicken collagen and found that these also reacted against the ligament tissue.

The thing is, so I read, she was a third rate academic who tripped over this extremely rare sample. She NEEDS to milk this for her career and ergo publications. It seems many of the tests she ran are pretty simply so far. I think she was trying to think of what she could do all by herself to get total credit and then try to form some collaborations where she can still get the maximum credit.

Anyway, that's some of what I read long ago.



Michael

The paper I read was that they used antibodies to Chicken collagen and found that these also reacted against the ligament tissue.


Yes, but that has nothing to do with DNA. That relates to the finding of soft tissue within dinosaur fossil bones that retains sufficient antigenic integrity to be recognised by antibodies in an IHC experiment. Antibodies against chicken collagen (supposedly) also recognised dinosaur collagen due to the highly conserved nature of collagen.

Mind you, I find it equally amazing that IHC can be performed on 88myo tissue as it is to extract DNA from an 88myo fossil. :eek:

the only way to prove its T-rex DNA rather than a more recent unknown insects DNA would be to grow it wouldnt it?

If this is the case (baring jurasic park of course) then this would be as unprovable as god is

the only way to prove its T-rex DNA rather than a more recent unknown insects DNA would be to grow it wouldnt it?

No. You're confusing science fiction with science reality.

Assuming DNA can be extracted, and assuming it’s usable, I imagine that sequencing of the DNA and phylogenetic/cladistic analysis of the sequences will verify whether it is dinosaur DNA or some other contaminating DNA from an extant source.

ok to ask a really stupid question but HOW?
We only know that human DNA is human because we have other human DNA to compare it too so its compleatly concivable that we could mestake dino DNA for the contaminate DNA we dont have a record for. If im wrong and there is some other way to verify it please correct me but the main way we verify things is either by DNA or by carbon dating as far as i know and you cant carbon date DNA

http://en.wikipedia.org/wiki/Molecular_phylogeny

well i read through that and it seems to agree with me, that contaminate DNA (ok not insect DNA) could well be mestaken for dino DNA as it relies on evolutionary pattens and we are still only SPECULATING that most Dinosaurs evolved into birds. We have no contempary relitives to compare it to and no DNA that can be varified to be contempary to the T-rex either for comparision. So basically if a unknown bird left DNA on the bones and we found it then we could quite easierly not only MESTAKE it for dino DNA but also try to use it as proof that dinosaures are related to birds (which could still be true but the contaminate couldnt be concidered proof)

We don’t need to make prior assumptions that birds evolved from dinosaurs. Phylogenetic analysis of DNA sequences will determine this for us. We have sequence information for modern birds against which the putative dino DNA sequence will be compared. Base pair substitutions (indicative of evolutionary time) will be present in the bird DNA that will place birds on a phylogenetic tree after dinosaurs.

see thats the problem. There is a huge gap between birds contempary to us and life contempary to the dinosaurse and so if we were to go back say, pre 1000 BC we could well find life that we have no previous record for. This would mean that even if its contaminate it would possably show the nessary markers

I understand that IHC would be assaying protein but surely if protein can stick around then so could some DNA? What ever happened to the whole Jurassic mossies idea? Did they ever extract dino DNA from mosquitoes?

No DNA that old is complete. It's fragmentary and not useful for sequencing, even if you could find some.

I understand that IHC would be assaying protein but surely if protein can stick around then so could some DNA? What ever happened to the whole Jurassic mossies idea? Did they ever extract dino DNA from mosquitoes?

Like these ?

http://www.don-lindsay-archive.org/creation/amber_work.jpg

It's interesting that, for example, pine resin has antibiotic properties.
http://www.cbc.ca/news/story/2001/10/16/pineheartburn_011016.html

No they didn't. Even in the unlikely chance that an insect would bite a dinosaur, the DNA is too fragmented to be useful.

No they didn't. Even in the unlikely chance that an insect would bite a dinosaur, the DNA is too fragmented to be useful.

They didn't what ?
I agree though.. but it's not an outlandish idea to research how much DNA is left in such insects, even if it is only their own.

They cannot sequence even the insect's DNA trapped in amber. DNA isn't that durable.

They cannot sequence even the insect's DNA trapped in amber. DNA isn't that durable.

Not even fragments ?

They can't put the fragments back together, they aren't useful.

They can't put the fragments back together, they aren't useful.

Yes, but it could be that they find a larger piece someday from which they can derive some information. It's not totally useless, right ?
Do you know whether or not research has been done on these type of fossils ?

It's fragmentary and not useful for sequencing, even if you could find some.


It's perfectly possible to sequence fragmented DNA. The degree of fragmentation/degradation is the issue.

if we were to go back say, pre 1000 BC we could well find life that we have no previous record for. This would mean that even if its contaminate it would possably show the nessary markers


Potentially, maybe. Without being any sort of expert in this area, I still think it would be possible to distinguish dinosaur DNA from many other unknown species that were contemporary to the dinosaurs. For example, I think we could distinguish dino DNA from mammalian, insect and fish DNA of unknown extinct species because of the strong molecular phylogenetic relationships and lineages we have for these evolutionary branches.


Edit: Oh, I just stumbled upon this by complete conicidence!

Protein shows chicken’s dino heritage - April 25, 2008 (http://blogs.nature.com/news/thegreatbeyond/2008/04/protein_shows_chickens_dino_he.html)

It’s hard to comment without any specific links or info. Here is an interesting Q&A in which dissolving fossil bones is mentioned a few times.

]

HR: not to say too much on just appearances, but she looks like a nutjob, she has that Tom Cruise look, d'ah

ok to ask a really stupid question but HOW?
We only know that human DNA is human because we have other human DNA to compare it too so its compleatly concivable that we could mestake dino DNA for the contaminate DNA we dont have a record for. If im wrong and there is some other way to verify it please correct me but the main way we verify things is either by DNA or by carbon dating as far as i know and you cant carbon date DNA


A: can I ask another stupid question, why is anyone entertaining & seriously discussing 65 million year old DNA? theres no way it could survive that long, it has to be contaminated, the implications are staggering
1. contaminated
2. hoax
3. miracle
4. young earth (Creationism)

use logic, postulate, hypothesize, theorize, whatever, lets get braincells firing

we have to answer these questions
under what ideal conditions could DNA survive for 65 million years intact,
then, was this sample found under these conditions,
was there a break in the chain of evidence (ok, too much CSI here, but could someone have contaminated the sample on purpose (Dr. Strange herself or someone trying to make her the fool)
could variant readings be had from the same sample (as a fossil under one test (real results) & as DNA with ATCG on an other (an error))?


nobody can't be seriously believing anything about this, can they?

whoa, I killed the discussion that fast?

I half expected a few people to explain, "that yes, DNA lasts 65 million years, frozen near absolute zero, happens all the time, see here, this sample I retreived last year with perfect veloraptor DNA, cloned it myself, it hisses at me when I feed it":D

I think that woman looks odd, some one pulled a joke on her, or maybe she is the joke:D