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Cloning extinct creatures.

Cainkane1

Philosopher
Cainkane1
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I was reading a scientific essay online when I read that the Neanderthal genome had been created. It was going to be possible sometime in the future to clone them. Is this ethical? How far along is this research? Is it possible to clone Mammoths or Mastadons? I was watching a show about the Indian legend of the Thunderbird and scientists think it was a giant condor weighing perhaps 200 lbs. Well they do have skeletal remains of this creature including several completely articulated skeletons. Wouldn't it be cool to bring this creature back? You could feed it leftover meat by products. What are your ideas on this?
 
Maybe before we start cloning extinct creatures, we should work on keeping the ones we still have. That way, when we do clone them, maybe they'll be here to stay.


Scientist: Let's clone passenger pigeons!

Layman: Cool! I'll go get my gun!
 
A (non gun-toting) layman's take on it:

At present, to make a clone you need the entire complement of nuclear DNA intact and an egg of the same species (the part with the mitochondrial DNA). I don't think we have that for any except the most recently extinct species. (And even then, you'd get one individual, and nothing like the diverse gene pool usually needed to establish a breeding population.)

The next best thing is, for example, to put the mammoth nuclear DNA into an egg from an elephant. Assuming that it works, the result is a kind of mostly-mammoth hybrid. If you take an egg from that hybrid and again put mammatho nuclear DNA into it, you get something closer to a mammoth.
 
I have heard that lots of organizations are banking cells, sperm and eggs if they can get them and some just somatic cells of the current species of animals under their care. These will be used to clone animals in an attempt to keep those species from going extinct. Once they get good at that then perhaps trying to revive a species that is banked but extinct would be the next step. At some point they will be skilled enough to attempt unbanked species.
 
Actually I was just reading Richard Dawkins' The Ancestor's Tale in which he mentions that DNA does not survive well over long periods of time even when frozen. 30,000 years for a frozen Neanderthal (and it was pretty incomplete due to deteriation), 400,000 for plants in permafrost were his stated records for oldest (barely viable) DNA. When not frozen it lasts a mater of days after death. So that pretty much rules out me having a pet Tyranosaurus Rex. And it rules out non-banked recently extincted species unless you can find one in an iceberg somewhere.
 
I don't think this is a good idea. A cloned extinct animal might come to life with the powers of telepathy and mind control, and then where would we be?
 
Spektator said:
I don't think this is a good idea. A cloned extinct animal might come to life with the powers of telepathy and mind control, and then where would we be?
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In a really lame episode of the Twilight Zone?
 
JoeTheJuggler said:
The next best thing is, for example, to put the mammoth nuclear DNA into an egg from an elephant. Assuming that it works, the result is a kind of mostly-mammoth hybrid. If you take an egg from that hybrid and again put mammatho nuclear DNA into it, you get something closer to a mammoth.
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The problem with this is that some DNA only exists outside the nucleus. No matter how many times you put mammoth DNA into a hybrid you will never be able to replace the mDNA with anything other than elephants.
 
mtDNA is very slow to diverge, since there's no chromosome shuffling or crossing over. So I guess there's a good chance that mammoth and elephant mtDNA would be pretty similar.

Also, what would the effect be of "incorrect" mtDNA? As long as the mitochondria break down ATP and release energy, isn't that the be-all and end-all for us eukaryotes? It's nuclear DNA that makes our superstructure - does it matter if the batteries are branded Ever Ready or Duracell?
 
I think there would be far more complex problems than mtDNA... The clones that were made of existing animals have very severe problems already, due to DNA demethylation. DNA methylation (plus its folding and association with histones) controls the expression levels of genes. DNA is a pretty resistant molecule (you need to put it in concentrated boiling HCl to denature it completely), but these fine-tuning mechanisms common to differentiated species are much more fragile.

It took many clones of the sheep Dolly to get a single viable embryo for this reason. There were actually malformations nobody had ever seen on subsequent clones (one had artheries with a diameter several times greater than normal... I can't find back the story, though).

the Kemist
 
There is also the matter of clones dying young because they were cloned with "old" DNA with shortened telomeres. I believe we still need to discover the trick of re-lengthening them.

[nitpick]By "artheries", presume you mean "arteries", KrazyKemist?[/nitpick] ;)
 
I think it all but inevitable that humans will eventually come to understand completely how DNA works (forgive me, Dr. Crick, RIP) and will at that point not only be able to bring back extinct species, we'll be able to create entirely new species out of whole cloth (so to speak). Bringing back the dodo is one thing. But can you imagine the ethical implications associated with creating a superintelligent flying shark that can speak, drive a taxicab, and tastes like lobster? (OK, so maybe that's a bit of a stretch, but you get my point.)

The technology may be 100 years or more in the future. But extrapolating all the advances we've made in our understanding of DNA over the last few decades, I'm firmly convinced it's coming. It could be an even more exciting/scary prospect than nuclear energy.
 
Cuddles said:
The problem with this is that some DNA only exists outside the nucleus. No matter how many times you put mammoth DNA into a hybrid you will never be able to replace the mDNA with anything other than elephants.
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If we can get the entire genome of a mammoth then we should be able to get the mitochondrial DNA also.
 
?

Even if successful, the ethical implications would make me think twice. Is a Neanderthal sentient and conscious? Would we accord it the same rights as homo sapiens? I'd need a much better reason than scientific curiosity before I'd open such a can of worms.
 
Graham Jackman said:
Even if successful, the ethical implications would make me think twice. Is a Neanderthal sentient and conscious? Would we accord it the same rights as homo sapiens? I'd need a much better reason than scientific curiosity before I'd open such a can of worms.
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I think we've got plenty of time to speculate about the possibility before needing to bring up ethical problems. But yeah, it'll have to be considered eventually, if it ever goes that far.
 
arthwollipot said:
I think we've got plenty of time to speculate about the possibility before needing to bring up ethical problems. But yeah, it'll have to be considered eventually, if it ever goes that far.
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Speculation is one thing, but any practical experiment requires that we confront the ethical issues. This is more than bringing a stray kitten home and being required to look after it. I think it's quite possible that we could eventually reconstruct something viable, that looks like the real thing, but how will we ever know that it is truly representative of the extinct species? Our information on the originals is so limited that we could never be sure. If we produce a single neanderthal, it will be forced to live an artificial existence even if we produce multiple individuals. Given the technology, I've no doubt someone will eventually try the experiment. My curiosity is not that boundless.
 
Dogdoctor said:
If we can get the entire genome of a mammoth then we should be able to get the mitochondrial DNA also.
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Unfortunately that doesn't seem to be the case. It is extremely hard to get any DNA from specimens that old, and mDNA is even worse than nuclear DNA. In any case, the method of cloning, as stated above, is to place nuclear DNA in an existing cell, which will already have its own mitochondria. As far as I know there is no way known of replacing the mitochondria, so even if we could get the DNA from them we wouldn't be able to do anything about it.

Big Al said:
mtDNA is very slow to diverge, since there's no chromosome shuffling or crossing over. So I guess there's a good chance that mammoth and elephant mtDNA would be pretty similar.
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Quite possibly. I suppose it depends how closely related elephants and mammoths were. Anyone know?

Also, what would the effect be of "incorrect" mtDNA? As long as the mitochondria break down ATP and release energy, isn't that the be-all and end-all for us eukaryotes? It's nuclear DNA that makes our superstructure - does it matter if the batteries are branded Ever Ready or Duracell?
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I think there's more to it than just being a battery, although not being a biologist I'm sure someone can correct me. It could be the difference not between brands of battery but between type of battery. Maybe elephants use AA and mammoths use D. The mitochondria may still work just fine, but they could be giving out the wrong amount of energy at the wrong rate. Combining similar animals of similar size should minimise this sort of problem, but I certainly wouldn't bet on it not being a problem at all.
 
And again, you'd have no more than a small handful of individuals. Unless mammoth DNA survives intact relatively commonly (probably not), you'd probably be trying to make a population out of one or two founders.

Assuming everything is is workable (which it probably isn't), it's doubtful you'd really be able to revive the species.
 
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