Jack Horner wants to make dinosaurs out of chickens

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Jack Horner wants to make dinosaurs out of chickens

Postby luvnotwar » Fri Sep 30, 2011 4:21 am UTC

http://www.wired.com/magazine/2011/09/ff_chickensaurus/all/1

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Re: Jack Horner wants to make dinosaurs out of chickens

Postby Gigano » Fri Sep 30, 2011 8:09 am UTC

If they do manage to genetically manipulate a line of chickens so they look like chickensauruses, it will probably take a very long time. But I doubt they'll even be able to produce a viable specimen that even closely resembles a dinosaur. It would be like trying to make a modern whale resemble basilosaurus. You'd probably have to change the animal too fast genetically for any visible result to emerge within a human lifetime.
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Re: Jack Horner wants to make dinosaurs out of chickens

Postby gmalivuk » Fri Sep 30, 2011 2:21 pm UTC

Gigano wrote:If they do manage to genetically manipulate a line of chickens so they look like chickensauruses, it will probably take a very long time.
Not if he's correct, and it's just a matter of reactivating genes that have been there all along.
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Re: Jack Horner wants to make dinosaurs out of chickens

Postby Angua » Fri Sep 30, 2011 2:23 pm UTC

After finding out about the availability and number of knockout (and knockin) mice and flies that you can get, I wouldn't be surprised if they managed to do this relatively quickly.
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Re: Jack Horner wants to make dinosaurs out of chickens

Postby mfb » Fri Sep 30, 2011 3:42 pm UTC

gmalivuk wrote:Not if he's correct, and it's just a matter of reactivating genes that have been there all along.

That the genes are available (but inactive) does not mean they will all work in a chicken. In other words: There might be some reason why they are inactive.


Maybe Horner should begin with something easier. Something less than 65 million years apart... cats into lions? (~5-10 million years) ;)

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Re: Jack Horner wants to make dinosaurs out of chickens

Postby Izawwlgood » Fri Sep 30, 2011 3:46 pm UTC

mfb wrote:That the genes are available (but inactive) does not mean they will all work in a chicken. In other words: There might be some reason why they are inactive.

I'm curious what you are basing this assumption on. Assuming that inactivated genes will have no effect is, in my mind, a larger leap than assuming that activating inactive genes will have an effect.

For example, the Platypus has genes for tooth enamel, because baby Platypus(es? odes?) have teeth. Those teeth fall out, and the genes are deactivated in adults.
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Re: Jack Horner wants to make dinosaurs out of chickens

Postby mfb » Fri Sep 30, 2011 4:06 pm UTC

?
All animals have parts of DNA which is not used (or just used for a certain time). Change that, and the organism can break down or get at least serious problems if you do it with the wrong parts. That is not an assumption, that is a fact.

To rephrase my post: You cannot just activate all genes you like to have and assume that the animal will live, look and work like a dinosaur.

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Re: Jack Horner wants to make dinosaurs out of chickens

Postby Izawwlgood » Fri Sep 30, 2011 4:10 pm UTC

mfb wrote:?
All animals have parts of DNA which is not used (or just used for a certain time). Change that, and the organism can break down or get at least serious problems if you do it with the wrong parts. That is not an assumption, that is a fact.

To rephrase my post: You cannot just activate all genes you like to have and assume that the animal will live, look and work like a dinosaur.

I don't think the guy is wantonly activating genes; he's specifically identified genes involved in tooth development, that are deactivated in birds and activated in reptiles, and is seeking techniques to activate those genes throughout an animals development. I think, anyway, because I haven't read the article but have heard about this quite a bit.

However, I assure you, I am aware that proper gene expression or silencing is quite important for organisms. What I am uncertain of, is why you assert that controlled activation of genes will NOT result in an effect. I can point you to a variety of literature wherein scientists activate normally deactivated genes (or vice versa) and get targeted effects without causing serious problems. Which isn't to say that serious problems *don't/can't* occur.
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Re: Jack Horner wants to make dinosaurs out of chickens

Postby Mr_Rose » Fri Sep 30, 2011 5:40 pm UTC

The trouble with activating tooth-genes "throughout development" is that your chickensaurus ends up as a ball of protoplasm and almost-teeth. You not only have to ID the gene and make sure the version found in your chickens hasn't drifted into uselessness or been re-used for some other process but also have to make sure your novel activator turns it on in the right places at the right times (I might be tempted to locate whatever cascade it is that makes beaks and crib that, but that's just me).

Also, I don't see where mfb asserted that activating the identified genes will "not result in an effect" - I think you are being excessively literal in your interpretation of what he said about them not all working. Perhaps if you took "work" in this context to mean "produce the desired effect" you might get closer to his intent?
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Re: Jack Horner wants to make dinosaurs out of chickens

Postby Izawwlgood » Fri Sep 30, 2011 6:08 pm UTC

Mr_Rose wrote:You not only have to ID the gene and make sure the version found in your chickens hasn't drifted into uselessness

True, which isn't terribly difficult to determine.
Mr_Rose wrote: been re-used for some other process

How do you mean?
Mr_Rose wrote:but also have to make sure your novel activator turns it on in the right places at the right times

Again, true, but not terribly difficult. There are a variety of assays that do exactly this.
The next step after identifying a transcription factor for 'tooth genes' would be inducing it's expression in beak progenitors.

But the point that makes this so interesting, is that it's evidently a straightforward pathway; if the gene is activated during development, you get teeth, if it's not, you get beaks. I wager a simple proof of negative would be silencing the gene in reptiles that have teeth, and seeing if you get non-toothed beak like mouth structures, and the 'simple' next step positive, would be either removing the silencing mechanism or inserting the activator.
Mr_Rose wrote:Perhaps if you took "work" in this context to mean "produce the desired effect" you might get closer to his intent?

No, I was responding to this claim:
mfb wrote:That the genes are available (but inactive) does not mean they will all work in a chicken. In other words: There might be some reason why they are inactive.

Which is a somewhat odd claim, given that A) there are species that have inactivated genes from their evolutionary history, such as the example I gave, that are fully functional, and B) That mfb is assuming the researchers haven't investigated the divergence of these teeth-making genes before trying to activate them is somewhat silly.
It'd be like me saying "Well, yeah, you could build a cantilevered roof, but you don't even know if your support struts will hold the weight" to an architectural engineer who told me he's going to build a new building.

EDIT: I just perused this particular article, and I wager mfb hasn't. There is an image of a bird skull with toothbuds.
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Re: Jack Horner wants to make dinosaurs out of chickens

Postby Charlie! » Fri Sep 30, 2011 7:56 pm UTC

Izawwlgood wrote:EDIT: I just perused this particular article, and I wager mfb hasn't. There is an image of a bird skull with toothbuds.

As it says in the article:
“Development has the capacity to remake a lot of things,” Harris says. “But what you lose are some of the last bits, like enamel and dentine, that are specific for teeth. You can’t even find a gene for enamel in the chicken genome.”

Carroll, the evo devo expert, shares that skepticism. He has done plenty of body-changing experiments on insects, manipulating the order and structure of development, and let’s just say that the resulting bugs are never happy. “It’s not like a Mr. Potato Head, where you just give it a tail and new hands and voilà: dinosaur,” Carroll says. “That tail has got to work with the rest of the body. There’s likely going to be some wiring problems, some coordination problems. Maybe some other body parts won’t develop normally.” He doesn’t disparage the imagination behind the idea and thinks that with enough money and time Horner might get something done, but “even if you raised an adult chicken with teeth, you’d really end up with nothing more than Foghorn Leghorn with teeth,” Carroll says. “And shitty teeth at that.”

That last is a great thing for a respected biologist to say :P
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Re: Jack Horner wants to make dinosaurs out of chickens

Postby Gigano » Sat Oct 01, 2011 8:56 am UTC

Izawwlgood wrote:
Mr_Rose wrote: been re-used for some other process

How do you mean?


I think he means genes that have lost their original ontology, and have evolved to become part of a different metabolic or signal transduction pathway. Genes in one organism may have different functions in another organism, even if they are closely related, just because some part of the gene has mutated.

I've become a bit more optimistic about this concept, by the way.
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Re: Jack Horner wants to make dinosaurs out of chickens

Postby mfb » Sat Oct 01, 2011 11:10 am UTC

Mr_Rose wrote:Also, I don't see where mfb asserted that activating the identified genes will "not result in an effect"

Same here. I never said that and I do not know why and how my posts are interpreted in that way.

>> I don't think the guy is wantonly activating genes
Neither do I. But that does not mean that it is an easy task.

>> A) there are species that have inactivated genes from their evolutionary history, such as the example I gave, that are fully functional
And there are species with inactivated genes that are not fully functional (or modified to be useful for other processes - or just broken as there was no evolutionary pressure to keep it working). What does Horner do if one of the crucial genes for chickensaurs is in that category?

>> B) That mfb is assuming the researchers haven't investigated the divergence of these teeth-making genes before trying to activate them is somewhat silly.
I do not assume that. I just assume that Horner did not succeeded yet, so problems may pop up in the process. It is like any other science project. Planning is one thing. Actually doing it is way more tricky.

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Re: Jack Horner wants to make dinosaurs out of chickens

Postby Izawwlgood » Sat Oct 01, 2011 2:20 pm UTC

Gigano wrote:Genes in one organism may have different functions in another organism

Curious; I'm not sure there's much example of this occurring. I mean, a signal may induce a slightly different pathway, or a pathway may have more or less complexity, but by in large, once, say, a gene evolves encoding a protein that facilitates the production of tooth enamel, chances are that same gene won't now encode a protein that serves as a differentiation factor for polarity gradients. I may be over thinking what you are trying to say though.

mfb wrote: I just assume that Horner did not succeeded yet

Again, look at the article; there is an image of two chicken skulls, one of which has teeth buds coming from it's beak. This isn't a dino-rooster, but it's a pretty good proof of concept.
mfb wrote:Neither do I. But that does not mean that it is an easy task.

I... what? No one is claiming science is easy, but your objections are more or less unscientific.
mfb wrote:Same here. I never said that and I do not know why and how my posts are interpreted in that way.

Because you said:
mfb wrote:That the genes are available (but inactive) does not mean they will all work in a chicken. In other words: There might be some reason why they are inactive.

Which I felt indicated that you were under the impression that inactivated genes, when activated, will have no effect. Because that is precisely what you are stating.
mfb wrote:And there are species with inactivated genes that are not fully functional (or modified to be useful for other processes - or just broken as there was no evolutionary pressure to keep it working). What does Horner do if one of the crucial genes for chickensaurs is in that category?

The crucial element I think you are missing is that scientists have identified a SINGLE GENE that when activated in reptiles causes tooth growth from mouth parts, and when inactive in birds (but still part of their genome!), means you end up with toothless beaks. Horner is experimenting with activating this factor to see if you can get teeth in birds, and preliminary results seem to indicate that yes you can. The reason this is interesting, is because it suggests that as populations develop, the inactivation of certain factors can result in different body phenotypes that may be better suited to the species new environment. There's a variety of proof of concept examples to draw from in various Developmental Biology or Embryology textbooks; species that have lost tails can be induced to grow them, or aquatic salamanders that when exposed to amphibian growth factors that are absent from their entire life cycle, lose their external gills and develop into terrestrial varieties.
The idea is that life and development is rather fluid. That a basic set of instructions and signals may be present for a given Family/Class, and when modified result in wildly different species.
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Re: Jack Horner wants to make dinosaurs out of chickens

Postby Charlie! » Sat Oct 01, 2011 5:57 pm UTC

Izawwlgood wrote:
mfb wrote: I just assume that Horner did not succeeded yet

Again, look at the article; there is an image of two chicken skulls, one of which has teeth buds coming from it's beak. This isn't a dino-rooster, but it's a pretty good proof of concept.

Of the dozens and dozens of parts of things needed to be done, it's not very surprising to have some of them be easy and already discovered. This does not at all mean that all other steps will be equally easy.

Izawwlgood wrote:single gene
If you read the quote I posted above, chickens lack the gene for enamel. So it's a little more work than turning on some genes.
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Re: Jack Horner wants to make dinosaurs out of chickens

Postby Gigano » Sat Oct 01, 2011 10:33 pm UTC

Izawwlgood wrote:
Gigano wrote:Genes in one organism may have different functions in another organism

Curious; I'm not sure there's much example of this occurring. I mean, a signal may induce a slightly different pathway, or a pathway may have more or less complexity, but by in large, once, say, a gene evolves encoding a protein that facilitates the production of tooth enamel, chances are that same gene won't now encode a protein that serves as a differentiation factor for polarity gradients. I may be over thinking what you are trying to say though.


I don't know of any example either, though it's possible it could have happened in some complicated way. And indeed it is not to be considered a serious point of discussion as I was merely trying to explain what Mr_Rose meant.
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Re: Jack Horner wants to make dinosaurs out of chickens

Postby Izawwlgood » Sat Oct 01, 2011 11:29 pm UTC

Charlie! wrote:Of the dozens and dozens of parts of things needed to be done, it's not very surprising to have some of them be easy and already discovered. This does not at all mean that all other steps will be equally easy.

I'm not claiming all/any steps would be easy. I'm pointing out that there are routine experimental protocols in place for identifying some of the 'difficulties' raised. Saying 'we need to know what transcription factors are' or 'what if the sequence is mutated' as a reason this cannot be done is more indicative of general ignorance of how biology works than being a cautious scientist.

Charlie! wrote:If you read the quote I posted above, chickens lack the gene for enamel. So it's a little more work than turning on some genes.

I'm not sure why you're pointing this out. I'm not claiming switching on a single gene will make a chicken a T-rex, I'm saying what the article is; that switching on a single gene results in teeth growing in beaks. Whether or not the teeth are properly formed or covered in enamel or useful for ripping out researchers eyeballs is another matter entirely.
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Re: Jack Horner wants to make dinosaurs out of chickens

Postby Charlie! » Sun Oct 02, 2011 5:08 am UTC

Charlie! wrote:If you read the quote I posted above, chickens lack the gene for enamel. So it's a little more work than turning on some genes.

I'm not sure why you're pointing this out. I'm not claiming switching on a single gene will make a chicken a T-rex, I'm saying what the article is; that switching on a single gene results in teeth growing in beaks. Whether or not the teeth are properly formed or covered in enamel or useful for ripping out researchers eyeballs is another matter entirely.

Sorry, I guess I assumed you were using "teeth" the same way the article was. For the structures mentioned in the article, the author just used the term "tooth buds."

I forget, Izzawlgood - do you have some kind of bio background? ADDED AFTER SOME LIGHT STALKING: Ah, yes you do.

So what sort of timeline do you see for making chickenosaurs? What I guess as an outsider is that to get something that developed properly you'd need a fairly good idea of how everything worked and have found the right genes for all the bits, which puts it on a 8+ year timescale, if you've just got one lab working on it.
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Re: Jack Horner wants to make dinosaurs out of chickens

Postby poxic » Sun Oct 02, 2011 5:27 am UTC

LIttle Jack Horner
Sat in a corner
Playing with DNA
He put in some homeodomain,
And pulled out an enantiornithine,
And said 'What a good boy I am today!'

/meh
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Re: Jack Horner wants to make dinosaurs out of chickens

Postby Izawwlgood » Sun Oct 02, 2011 7:49 am UTC

Charlie! wrote:Sorry, I guess I assumed you were using "teeth" the same way the article was. For the structures mentioned in the article, the author just used the term "tooth buds."

Am I not? It seems like the article used 'teeth' to indicate 'potential for tooth-like structures'. Are we talking about different things?
Charlie! wrote:do you have some kind of bio background?

Yes. I'm a grad student pursuing a degree in molecular cell biology. I work on flies and neurons, for whatever that's worth.
Charlie! wrote:So what sort of timeline do you see for making chickenosaurs? What I guess as an outsider is that to get something that developed properly you'd need a fairly good idea of how everything worked and have found the right genes for all the bits, which puts it on a 8+ year timescale, if you've just got one lab working on it.

Honestly, that's a big speculative. I'd say based on the article and other articles I've read on this topic that a chicken with functional teeth was only a funding issue away, but I could be wrong. If they've identified these genes, and demonstrated that their activation in transgenic chicken causes formation of teeth buds, I can't imagine they're terribly far off from demonstrating other aspects of the animals tooth development as a function of this genes activation. But I dunno, I'm not in the field; for all I know, chicken is a particularly difficult model organism to work with.

What I do know is that a number of organisms have been demonstrated to have wildly differing phenotypic pathways based on both exo and endogenous signaling, despite genotypic similarities, and that this work indicates a close evolutionary timeline between birds and reptiles. It indicates that an existent species can be changed by simply deactivating a gene pathway.
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Re: Jack Horner wants to make dinosaurs out of chickens

Postby mfb » Sun Oct 02, 2011 9:48 pm UTC

Izawwlgood wrote:
mfb wrote: I just assume that Horner did not succeeded yet

Again, look at the article; there is an image of two chicken skulls, one of which has teeth buds coming from it's beak. This isn't a dino-rooster, but it's a pretty good proof of concept.

It is a proof that genes can be activated and give the wanted results. Was that really new? But it is only one small step - maybe the easiest, as they chose to do that first.
So what part of "I just assume that Horner did not succeeded yet" is wrong?

>> No one is claiming science is easy
So where is your problem with my statement of that? Especially if it is under a quote of "[...] just a matter of reactivating genes that have been there all along [...]"

mfb wrote:That the genes are available (but inactive) does not mean they will all work in a chicken. In other words: There might be some reason why they are inactive.

Let me rephrase that again:
It is possible (!) that some (!) inactive genes, once activated, may not work [in the way the scientist want them to work].
Look at the logic - it is the same statement and it was that all the time.

The opposite would be "just activate all genes you like and you can be sure they will all work in the right way to give you a chickensaur". Do you really think that is true?

The crucial element I think you are missing is that scientists have identified a SINGLE GENE that when activated in reptiles causes tooth growth from mouth parts, and when inactive in birds (but still part of their genome!), means you end up with toothless beaks. Horner is experimenting with activating this factor to see if you can get teeth in birds, and preliminary results seem to indicate that yes you can. The reason this is interesting, is because it suggests that as populations develop, the inactivation of certain factors can result in different body phenotypes that may be better suited to the species new environment. There's a variety of proof of concept examples to draw from in various Developmental Biology or Embryology textbooks; species that have lost tails can be induced to grow them, or aquatic salamanders that when exposed to amphibian growth factors that are absent from their entire life cycle, lose their external gills and develop into terrestrial varieties.
The idea is that life and development is rather fluid. That a basic set of instructions and signals may be present for a given Family/Class, and when modified result in wildly different species.

But that is a proof by example. Some integers like 2 (teeth), 3 (tails) and 5 (amphibian stuff) are prime, but that does not mean that all integers are. Teeth are nice, but not all Horner needs for chickensaurs, right?


Saying [whatever] as a reason this cannot be done [...]

Who said that?

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Re: Jack Horner wants to make dinosaurs out of chickens

Postby Izawwlgood » Sun Oct 02, 2011 10:03 pm UTC

mfb wrote:So what part of "I just assume that Horner did not succeeded yet" is wrong?

The part where there's a chicken with teeth buds coming from it's beak because of gene activation. Like what is said in the article.

mfb wrote:Let me rephrase that again:
It is possible (!) that some (!) inactive genes, once activated, may not work [in the way the scientist want them to work].
Look at the logic - it is the same statement and it was that all the time.

The opposite would be "just activate all genes you like and you can be sure they will all work in the right way to give you a chickensaur". Do you really think that is true?

Because you listed this contention as a reason why it couldn't/wouldn't work, despite the evidence that it already had. Also, your statement that 'it is possible that some things may not do what you think they do' is different from your statement that:
mfb wrote:That the genes are available (but inactive) does not mean they will all work in a chicken. In other words: There might be some reason why they are inactive.

Admittedly this may be a language thing, and I may have misread what you were saying here.

mfb wrote:The opposite would be "just activate all genes you like and you can be sure they will all work in the right way to give you a chickensaur". Do you really think that is true?

No, which is why myself or Horner never claimed this to be the path to get a chicken with teeth developing in it's beak. What is curious to me is that the article has stated that a single gene has been identified which when activated, causes tooth growth in the beaks of birds, is present and activated in reptiles, and is present but inactivated in birds. Scientists have experimentally activated the gene in birds and gotten teeth, and you are still claiming that this is unlikely, or won't act the way you want it to, or whatever else it is you are having issues with.
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Re: Jack Horner wants to make dinosaurs out of chickens

Postby jmorgan3 » Mon Oct 03, 2011 12:35 am UTC

Izawwlgood wrote:What is curious to me is that the article has stated that a single gene has been identified which when activated, causes tooth growth in the beaks of birds, is present and activated in reptiles, and is present but inactivated in birds. Scientists have experimentally activated the gene in birds and gotten teeth, and you are still claiming that this is unlikely, or won't act the way you want it to, or whatever else it is you are having issues with.

This bit from the article bears repeating (emphasis mine):
Dr. Matthew Harris, the guy who discovered the toothlike buds wrote:“Development has the capacity to remake a lot of things,” Harris says. “But what you lose are some of the last bits, like enamel and dentine, that are specific for teeth. You can’t even find a gene for enamel in the chicken genome.
They have not made chickens with teeth, they have made chickens with toothlike buds. They lack the genes for encoding a very important component of teeth, and therefore it is impossible to make a chicken with teeth just by activating existing genes (and that's all Horner plans to do).

Teeth are just one difference between chickens and dinosaurs. Each difference is likely the result of several gene deactivations over the past 70-odd million years. Once a gene is inactive for the animal's whole lifetime, there is no evolutionary pressure against mutations in that gene which eliminate it or make it useless for its original function, e.g. the gene for dentine in chickens, above. Making a dinosaur from a chicken in the way Horner proposes requires that every active dinosaur gene remain, unaltered, in the chicken genome, just waiting to be turned back on, despite 70 million years of accumulated non-selected-against mutations. We know that this is not the case, because the dentin gene has been lost, and there are probably a lot of other lost genes as well.
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Re: Jack Horner wants to make dinosaurs out of chickens

Postby Izawwlgood » Mon Oct 03, 2011 12:44 am UTC

jmorgan3 wrote:They have not made chickens with teeth, they have made chickens with toothlike buds. They lack the genes for encoding a very important component of teeth, and therefore it is impossible to make a chicken with teeth just by activating existing genes (and that's all Horner plans to do).

Repeat it all you want; I said the very same thing. In fact, look up a little ways.
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Re: Jack Horner wants to make dinosaurs out of chickens

Postby jmorgan3 » Mon Oct 03, 2011 12:59 am UTC

Care to respond to the remaining majority of my post, where I point out that for Horner to succeed, a million little things have to have gone exactly right, and that we know that at least one of those things has not gone exactly right?
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Re: Jack Horner wants to make dinosaurs out of chickens

Postby Izawwlgood » Mon Oct 03, 2011 2:06 am UTC

What are you referring to? No one is positing that activating the gene makes teeth; what was demonstrated (years ago, I should add: the first set of papers on this started making rounds in 2003 or so) is that activating a single gene initiates tooth growth.

So what are these 'million things that haven't gone right'?

Has anyone bothered doing a bit of poking around about this? Just google 'chicken teeth gene' and you'll get tons of hits spanning roughly a decade about this.
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Re: Jack Horner wants to make dinosaurs out of chickens

Postby jmorgan3 » Mon Oct 03, 2011 2:23 am UTC

Izawwlgood wrote:What are you referring to? No one is positing that activating the gene makes teeth;
Jack Horner is positing that activating a whole bunch of chicken genes will create a dinosaur. So, what I'm referring to is
jmorgan3 wrote:Making a dinosaur from a chicken in the way Horner proposes
, also conveniently located in the title of this thread.
Izawwlgood wrote:So what are these 'million things that haven't gone right'?

I never wrote the text in your quote, and it is not an accurate paraphrase. For Horner's task to be possible, a million things have to have gone right (each of a bunch of genes not mutating despite a total lack of evolutionary pressure), and we know that one of those required things didn't happen (the dentin gene did mutate or disappear). That alone means his task is impossible. Knowing this, the best case scenario is making an organism similar to a dinosaur except without dentin, and that presumes that all the other genes are intact.
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Re: Jack Horner wants to make dinosaurs out of chickens

Postby Izawwlgood » Mon Oct 03, 2011 3:03 am UTC

jmorgan3 wrote:Jack Horner is positing that activating a whole bunch of chicken genes will create a dinosaur. So, what I'm referring to is

No, he's positing that modifying a chicken will create a dinosaur. Activating deactivated genes (and I wager, silencing active genes) are just one of the tools he plans on using, because of the neat observation and a single gene, when activated, initiates tooth growth.
So, again, no one is positing that activating a single gene gets you fully functional teeth. Horner is interested in creating a dinosaur, from a Aves template, and this interest was piqued because of the assumption that birds are close relatives of dinosaurs, and the observation that many genetic similarities are likely still present.

jmorgan3 wrote:For Horner's task to be possible, a million things have to have gone right (each of a bunch of genes not mutating despite a total lack of evolutionary pressure)

No, for Horners task to be possible we need to facilitate a better understanding of embryology and development. What he's proposing sounds difficult, but everything from unfusing wing digits to elongating tails, reducing feather growth, and indeed, inducing tooth development, are all developmental steps/processes that are likely not entirely shrouded in mystery.
jmorgan3 wrote: That alone means his task is impossible.

Only if your goal is to get teeth solely by activating this single gene.
jmorgan3 wrote:Knowing this, the best case scenario is making an organism similar to a dinosaur except without dentin, and that presumes that all the other genes are intact.

No, knowing this, the best case scenario is gaining further understanding of the processes required for various organismal developments, engineering an organism from a bird template that has many features similar to a target dinosaur, like teeth, tails, grasping limbs, and saying "Damn, that shit is cool"
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Re: Jack Horner wants to make dinosaurs out of chickens

Postby jmorgan3 » Mon Oct 03, 2011 3:39 am UTC

Izawwlgood wrote:
jmorgan3 wrote:Jack Horner is positing that activating a whole bunch of chicken genes will create a dinosaur. So, what I'm referring to is

No, he's positing that modifying a chicken will create a dinosaur. Activating deactivated genes (and I wager, silencing active genes) are just one of the tools he plans on using

Which other tools? The article doesn't mention any other tools, and it also explicitly rules out genetic engineering:
Article wrote:he intends to twerk only development and not alter the DNA itself


Izawwlgood wrote:No, for Horners task to be possible we need to facilitate a better understanding of embryology and development. What he's proposing sounds difficult, but everything from unfusing wing digits to elongating tails, reducing feather growth, and indeed, inducing tooth development, are all developmental steps/processes that are likely not entirely shrouded in mystery.


I don't doubt that Horner can probably make important steps along these lines, and reveal a lot about evolution on the way. However, there are doubtless important genes somewhere along the process which have become irretrievably garbled, and how do you fix that without genetic engineering?

Izawwlgood wrote:Only if your goal is to get teeth solely by activating this single gene.

If your goal is to make a whole dinosaur, then a necessary sub-goal will be making dinosaur teeth. You can't make dinosaur teeth without a gene for dentin. Chickens do not have the gene for dentin, and you can't give it back to them without changing their DNA, which Horner will not do. Therefore, Horner can't make them grow dinosaur teeth. Therefore, Horner can't make a dinosaur out of a chicken. Where am I wrong?

Izawwlgood wrote:No, knowing this, the best case scenario is gaining further understanding of the processes required for various organismal developments, engineering an organism from a bird template that has many features similar to a target dinosaur, like teeth, tails, grasping limbs, and saying "Damn, that shit is cool"
It sounds like you're agreeing with me here, that Horner can't make a full dinosaur, only "step back" some features some of the way back into evolutionary history.
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Re: Jack Horner wants to make dinosaurs out of chickens

Postby gmalivuk » Mon Oct 03, 2011 4:14 am UTC

jmorgan3 wrote:It sounds like you're agreeing with me here, that Horner can't make a full dinosaur.
Well, yeah. I don't think anyone was seriously suggesting he'd make a full and complete dinosaur by flipping a few genetic switches.
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Re: Jack Horner wants to make dinosaurs out of chickens

Postby Charlie! » Mon Oct 03, 2011 6:41 am UTC

gmalivuk wrote:
jmorgan3 wrote:It sounds like you're agreeing with me here, that Horner can't make a full dinosaur.
Well, yeah. I don't think anyone was seriously suggesting he'd make a full and complete dinosaur by flipping a few genetic switches.

I think Izzawlgood in fact denied that he wouldn't (for sufficiently un-true-scotsmany definitions of "full and complete"), but that was probably just getting carried away arguing.
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Re: Jack Horner wants to make dinosaurs out of chickens

Postby Izawwlgood » Mon Oct 03, 2011 12:47 pm UTC

Really? Where? I don't think I ever claimed a full dinosaur would occur from a single gene modification.

jmorgan3 wrote:Which other tools? The article doesn't mention any other tools, and it also explicitly rules out genetic engineering:

I didn't see that line. My guess is that it's actually just bad scientific reporting; the paper on the the original finding(2006, my mistake) are investigating a genetic mutant. The various changes Horner is talking about (digital fusions, tail development, etc) aren't going to due to random mutations and clever chicken husbandry.
But now I'm confused; how do you alter development, including activating an inactive gene, without genetic engineering?
EDIT: It is bad reporting; if you view the video, Horner talks about gene knock outs. While he's talking about the process of gene discovery, he then also claims to want to get the three phenotypes in a single organism.
jmorgan3 wrote:If your goal is to make a whole dinosaur, then a necessary sub-goal will be making dinosaur teeth. You can't make dinosaur teeth without a gene for dentin. Chickens do not have the gene for dentin, and you can't give it back to them without changing their DNA, which Horner will not do. Therefore, Horner can't make them grow dinosaur teeth. Therefore, Horner can't make a dinosaur out of a chicken. Where am I wrong?

You aren't; it was never my assumption that this goal wouldn't include genetic modification. If various genes required for something Horner wants are absent in chicken, those genes will obviously have to be reintroduced. The original finding was interesting because it suggests that developmentally, there is a single gene to initiate tooth development, and birds, being a recent offshoot from dinosaurs, simply switched this gene off. The claim is NOT that the only difference between birds and dinosaurs is this single gene.
jmorgan3 wrote:It sounds like you're agreeing with me here, that Horner can't make a full dinosaur, only "step back" some features some of the way back into evolutionary history.

Yes. And it is interesting because it aims to demonstrate that development of evolutionarily closely related lineages are potentially labile. Axolotls and Salamanders. Birds and Dinosaurs. I would further suggest that this sort of research is 'useful' because of the plethora of developmental issues that plague humanity; a better understanding of how these steps occur, and better tools or experience in modifying them, could potentially give us ways to fix them.
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Re: Jack Horner wants to make dinosaurs out of chickens

Postby mfb » Mon Oct 03, 2011 2:36 pm UTC

Izawwlgood wrote:
mfb wrote:So what part of "I just assume that Horner did not succeeded yet" is wrong?

The part where there's a chicken with teeth buds coming from it's beak because of gene activation. Like what is said in the article.

I do not call chickens with teeth buds (or even full teeth) "chickensaurs". There are many parts missing for that.

>> Because you listed this contention as a reason why it couldn't/wouldn't work
No I did not. I just listed it as possible obstacle on the way.

>>despite the evidence that it already had.
Only a tiny step worked. That is not an evidence that all other steps will work, too. That is the whole point here.

>> Admittedly this may be a language thing, and I may have misread what you were saying here.
I think so.

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Re: Jack Horner wants to make dinosaurs out of chickens

Postby Izawwlgood » Mon Oct 03, 2011 2:51 pm UTC

There's definitely some kind of language barrier here mfb.
mfb wrote:I do not call chickens with teeth buds (or even full teeth) "chickensaurs". There are many parts missing for that.

The 'success' that we were referring to when you said that he hadn't succeeded, was developing a chicken that has tooth formation. You were indicating that he hadn't succeeded at creating a chicken that had tooth formation, and I was pointing out to you that the article has an image of a chicken skull with developing teeth.

mfb wrote:>> Because you listed this contention as a reason why it couldn't/wouldn't work
No I did not. I just listed it as possible obstacle on the way.

No, on the topic of tooth formation in chickens, you claimed;
mfb wrote:That the genes are available (but inactive) does not mean they will all work in a chicken. In other words: There might be some reason why they are inactive.

Which is what I originally contended.

mfb wrote:>>despite the evidence that it already had.
Only a tiny step worked. That is not an evidence that all other steps will work, too. That is the whole point here.

Yes, that is the whole point; which is why Horner is working on making other things happen. The article wasn't a 'LOOK, CHICKENDINOSAURS!', it was a 'This guy is trying to make a rudimentary dinosaur from a chicken, and look, here is one cool thing that's been demonstrated already'.
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Re: Jack Horner wants to make dinosaurs out of chickens

Postby mfb » Tue Oct 04, 2011 8:39 am UTC

>> The 'success' that we were referring to when you said that he hadn't succeeded, was developing a chicken that has tooth formation.
The 'success' I talk about is the "chickensaur". It is your interpretation of my post if you refer to something else.

Izawwlgood wrote:
mfb wrote:>> Because you listed this contention as a reason why it couldn't/wouldn't work
No I did not. I just listed it as possible obstacle on the way.

No, on the topic of tooth formation in chickens, you claimed;
mfb wrote:That the genes are available (but inactive) does not mean they will all work in a chicken. In other words: There might be some reason why they are inactive.

Which is what I originally contended.

Sorry, but if you don't understand my statement, it is useless to discuss it further. If you would, there would be no discussion at all. This is my last comment on that, there is no point in adding more. Just a last hint: A different placement of the word "not" would change the meaning of it completely, so its position is important here.

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Re: Jack Horner wants to make dinosaurs out of chickens

Postby Izawwlgood » Tue Oct 04, 2011 1:13 pm UTC

If you can't communicate clearly or use language to convey your thoughts concisely, yes, there is no reason to discuss this further.

I sent the article and the original 2006 paper to my Dev Bio professor (hilariously enough, the class I am taking right now), who thought it was neat, but a very long term goal.
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