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Science

Cenozoic Park: Cloning the Tasmanian Tiger 385

Posted by michael from the velociraptor-up-next dept.
Mirk writes "The Australian Museum reports a breakthrough in their plans to clone the Tasmanian Tiger. The ``tiger'', actually a carnivorous marsupial, became extinct in 1936, when the last known specimen died in captivity. Er, did I say ``extinct''? Now it looks like what everyone thought was an extinction may be ``a 70-year hiccup'', to quote the press release. The museum's Evolutionary Biology Unit have successfully replicated individual Tasmanian Tiger genes using a process known as PCR (Polymerase Chain Reaction)."
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Cenozoic Park: Cloning the Tasmanian Tiger More

Cenozoic Park: Cloning the Tasmanian Tiger

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  • I really hope (Score:3, Insightful)

    by Anonymous Coward on Tuesday May 28, 2002 @09:34AM (#3594723)
    Scientists don't go around cloning every extinct animal. Not every animal died because of evil humans, some died because they weren't fit to survive in this world. Bringing them back now, when other species have evolved, could throw everything off balance and screw up the world even more.

    Just because you can do something, doesn't mean you should.

    • Re:I really hope (Score:2, Interesting)

      by coryboehne ( 244614 )
      I have no doubt that careful judgement will be used in deciding what animals this would be applied to, and there is little doubt that the demise of the tasmanian tiger was caused by human interference.

      • Re:I really hope (Score:2, Insightful)

        by Anonymous Coward
        "Boy, having this extinct animal sure would make a lot of money and exposure for our zoo/park... Should we do it?"
    • But if it became extinct in the last 100 or 150 years, chances are likely that it was humans. And it's doubtful that a whole lot of evolution would occur in that short of a timespan.

      I don't think there is much wrong in correcting a past mistake.
      • But if it became extinct in the last 100 or 150 years, chances are likely that it was humans
        In this case you can ring up the people involved in the extinction and ask them to tell you stories about trapping the creatures as youngsters - but be careful to check the time difference. Not many people in their nineties have email, but you never know.

    • Look at the introduction of 'foreign' species... (Score:5, Insightful)

      by teambpsi ( 307527 ) on Tuesday May 28, 2002 @09:48AM (#3594828) Homepage
      All you really need to do is look at the track record of the introduction of foreign species into environments that had not evolved with them.

      Take Hawaii (okay, share it with the rest of us ;) -- the introduction of the mongoose to fight the rat population in the sugar cane fields has had a negative impact on the native bird populations.

      Or to quote my favorite Jeff Goldblum line:

      "You were so busy trying to see if you could do it that you didn't stop to think about whether you should."
      • Skinner: Well, I was wrong. The lizards are a godsend.
        Lisa: But isn't that a bit short-sighted? What happens when we're overrun by lizards?
        Skinner: No problem. We simply release wave after wave of Chinese needle snakes. They'll wipe out the lizards.
        Lisa: But aren't the snakes even worse?
        Skinner: Yes, but we're prepared for that. We've lined up a fabulous type of gorilla that thrives on snake meat.
        Lisa: But then we're stuck with gorillas!
        Skinner: No, that's the beautiful part. When wintertime rolls around, the gorillas simply freeze to death.
    • Not every animal died because of evil humans
      This one certainly did - although I would say incredibly shortsighted instead of evil.

      There are still occasional sightings of dog-like critters where the Thylacine roamed, but they are probably foxes.

      The recently deceased David Fleay was particularly proud of, among other things, breeding platypus and having a big scar on his bum from when he was bitten by a Thylacine.

    • Re:I really hope (Score:4, Insightful)

      by Daniel Dvorkin ( 106857 ) on Tuesday May 28, 2002 @10:22AM (#3595021) Homepage Journal
      [sigh]

      As another poster pointed out, the Tasmanian Tiger was in fact hunted to extinction (or possibly near-extinction, but recent sightings in the wild are unconfirmed) by humans -- there's no doubt about that. But that's not really the point. The real point is that whether or not an animal is "fit to survive in this world" is determined by one thing and one thing only, and that is, well, survival. If an animal goes extinct, for whatever reason, it is unfit. If it comes back, in any manner, it is by definition fit again. It's really that simple.

      Many varieties of domesticated animals, from housecats to beef cattle, have been bred to be so different from their wild ancestors that the species would have significant trouble surviving without humans around to take care of them. Does this mean they're unfit? Of course not. It means they're perfectly fit for our current, human-dominated world.
    • ...outside of a very controlled environment like zoos and labs.

      These particular animals were exterminated because they were pests. Even the 70yrs they've been out of commision is probably enough to keep them surviving again in the wild.

      But then again, just the other day, here in the Boston area I saw my first coyote. Go figure...
    • Not every animal died because of evil humans, some died because they weren't fit to survive in this world.

      Yes, just think of the Pygmy Shrew [pox.co.uk]!
    • And why would it matter if they died because of evil humans? Evil humans are as much a part of nature as all other predators. There is no distinction between animals that died "because the weren't fit to survive in this world" and animals that died because of humans. Those animals that died because of humans obviously are not fit to live in this world either, a world occupied by "evil humans".

    • Re:I really hope (Score:2, Insightful)

      by QuMa ( 19440 )
      And on the same grounds, the fact that it gets reintroduced means it was in fact fit after all, as the only thing that determines is living on. And as we (apparantly) decided to reintroduce it, it's perfectly fit.

      Bottom line: We're not influencing the system, we're part of it.

      (sub-bottom-line: The question of whether we want the Tas. Tiger in our world is a different one, but don't claim we shouldn't because of a 'sin against evolution'.)

    • A complete misunderstanding of natural history (Score:5, Insightful)

      by DevilsEngine ( 581977 ) on Tuesday May 28, 2002 @01:06PM (#3596398)
      "Not every animal died because of evil humans, some died because they weren't fit to survive in this world."

      Fitness to survive in the world has nothing to do with it. A meteor falls, and everything with a body mass greater than 100kg dies out. Were the larger animals less fit? A volcano erupts. A species dies. A flood wipes out a nesting ground. Chalk up another one. Human sailors bring in rats, goats and row plants, destroying practically all native flora and fauna of whole island chains.

      Were any of these things destroyed because they were less fit? Of course not. If your building catches on fire, are the survivors more "fit" or are they simply lucky enough to be working on the first floor?

      Despite the pitifully bad dialog of Jurassic Park, natural history does not represent some featureless plain on which species struggle against each other and the best win out. Catastrophes happen. Climates make sudden, radical shifts. Disease runs rampant. New vegetation suites are established. Chance is everywhere.

      And chance is all it takes. Abandon any idea that the creatures you see around you are "better" than what came before. Different? Sure. Better? By what standards? They're here because of chance built on chance, built on chance. Feedback loops tend to enforce the status quo, keeping many species stable over millions of years (a feature generally absent for the last 12,000 years) but the best predator on Earth can't live if all the prey die and forest dwellers die when the forest goes bye.

      The Thylacine happened to be a predator on an island where humans decided to raise sheep. It was fully "fit" in the environment before this point. Afterwards, it was "unfit" in the sense that it's hide was not bulletproof and it had an unfortunate predilection for traps.

      Should we worry about the return of extinct species? At some point, yes, but not because some anthropomorphic "nature" selected them for extinction. We should worry because these creatures may be all too "fit" and have behaviors, breeding strategies, or feeding habits that are exceptionally successful in a modern setting.

      Do you oppose the return of Grey Wolves to the Yellowstone Basin, or the reintroduction of Grizzlies to their historic range? Like the thylacine, these are creatures that have been absent from these territories for multiple generations. And the areas to which they are being "returned" have often experienced radical changes in the intervening years. Watching the ups and downs of these "reintroduction" projects should give us a good preview of the pitfalls to avoid when someone wants to put just a few Mastadons in Missouri.

    • Insightful? (Score:3, Insightful)

      by hey! ( 33014 )
      This is just the atheist's version of the religious argument that science should "not play God." Something infinitely wiser than us has not ordained that something should be, therefore man should not rightly make it be.

  • Wow... (Score:5, Funny)

    by ImaLamer ( 260199 ) <john.lamar@g m a i l . com> on Tuesday May 28, 2002 @09:35AM (#3594731) Homepage Journal
    State funded cloning... kinda like a movie I just watched yesterday.

  • Why bother? (Score:2, Funny)

    by L. VeGas ( 580015 )
    Bugs Bunny will just kill it again.
  • Indeed this is a great solution if they can just get it to work properly and be able to breed the offspring. Of course as far as I know no-one has yet tried to breed animals that have been created through cloning procedures, and for a species to become viable this is an obvious must, however once this hurdle is cleared there are great possibilities as to what damage we can undo. Next up, the dodo bird.
  • and we will get a choice at the thanksgiving !
  • ...but they won't be.

    Environmental activism is supposed to be all about preserving "Earth's delicate balance," of which extinction is a natural, and vital process.

    But, of course, they'll overlook that if it means injecting a cutesy-woosty puddy-tat back into a wild that no longer finds the critter-witter necessary, because we got one over on the evil-weevil human beings.

    *shrug*
    • That's not necessarily true. Environmental Activism is about removing our influence from the world. Environmentalists seem to think that it's not fair that we evolved to have larger, more complex brains and more supple fingers than other creatures, and so we should re-level the playing field by making special concessions.

      We've hunted species to extinction, both for our protection, and for our mere convenience. Dire wolves, for example. We almost hunted the Elk to extinction, but now they're a big pain in the ass again due to management efforts. Likewise buffalo, which you can buy in ground form in many restaurants, in a bun with a little produce and some sauces.

      So bringing back any species which humanity has clearly driven to extinction (I don't know if this is one of them) is well within the bounds of environmental activism.

      • Environmental Activism is about removing our influence from the world. Environmentalists seem to think that it's not fair that we evolved to have larger, more complex brains and more supple fingers than other creatures, and so we should re-level the playing field by making special concessions.

        You're only correct in regard to the simplistic interpretation of environmentalism - an interpretation that I think is doing more harm than good, because it is so easily ignored. As it should be.

        Environmentalism is really an activist viewpoint on ecological balance. The idea is to keep in mind that the function of our environment - and therefore our own function - is extremely complex. It's far too complex for us to model. In this way, environmentalism is a very *conservative* (hey, conservation!) position. "Better safe than sorry" could be the primary mission statement.

        The point is just that we really don't know what's going to result from our actions, and so we'd best come at the whole problem scientifically, carefully. Knee-jerk, reactionary thought is as big a problem within the environmental movement as it is without.

        So, repetitively: environmentalism is a logical extension of scientific method.

        I'm really getting sick of otherwise intelligent people assuming that there is no logical basis for environmentalism simply because they associate it with stupid and often quite stinky people.

    • Ok, sometimes I just can't help feeding the trolls, so here goes...

      Ever heard of something called the Precautionary Principle [ratical.org]? It's a risk/hazard assessment method becoming common (it's already law for certain things in the EU) for environmental (and other) use around the world, and it looks at ways of minimizing risks, hazards, and above all, harm, which is really what environmentalism is about, not a bleeding-heart slavish devotion to "cute."

      As for myself, speaking as at least some kind of an environmentalist, I'm not sure injecting extinct animals back into the ecosystem (which is a very heavy system, go read your systems theory again) is a good idea. At best, it should only happen after a thorough risk/hazard assessment, including long-term second and onward order results modelling, and then only if there's no "reasonable doubt."

      On the bright side, it doesn't look as though they're far enough along with this project to warrant serious paranoia...yet.

      Oh, and...the thing wasn't a "puddy tat." It was a carnivorous marsupial; hardly the kind of thing I'd want in my bed, and probably not (judging by other marsupials) cute in the least, and it probably got the name "tiger" because of the non-cute tiger-like traits it had (hunting, killing, perhaps?). So, please, a little credit?
    • I don't think this is the example you are looking for. The reason the Tasmanian Tiger became extict is that the Tasmainian state government put a bounty on them because the state's farmers believed they were killing sheep (which thay may have been but certainly not in great numbers). So I can hardly see how reintroducing them on the island would damage "Earth's delicate balance", and they couldn't possibly do more damage than the introduced sheep currently do. Although the Tasmanian wilderness seems to have survived without the this particular animal, I'm sure the human race, and the earth as a whole, would be better off with anything that helps reduce the dramatic decline in bio-diversity. BTW like most Australian native fauna, I wouldn't call the Tasmanian Tiger "cutesy-wootsy", nor a marsupial a "puddy-tat". You should come visit and have a look at some of our animals face-to-face.
    • Environmental activism is supposed to be all about preserving "Earth's delicate balance," of which extinction is a natural, and vital process.

      Now that I agree with. Humans are a part of the environment, therefore, our impact on the environment is natural.

      But, of course, they'll overlook that if it means injecting a cutesy-woosty puddy-tat back into a wild that no longer finds the critter-witter necessary, because we got one over on the evil-weevil human beings.

      That's a little over-stated, but humans did HUNT them to extention. I don't feel we have a moral responsibility to save/regenerate the species, but I think this is the closest case to it

      Now, aren't Kangaroo's major pests? Can these things live on Kangaroo's?

      If they're that fierce, maybe they can help with the deer population problems [jsonline.com] in Wisconsin :)

  • uh oh.... (Score:2)

    by ct ( 85606 )
    Next stop... Serpentor [starwars-rpg.net]

  • Cloning (Score:2, Funny)

    by Arsewiper ( 535175 )
    The Vatican claims to have the original forskin of Jesus. They should clone that for an all-round Second Coming.

    "The corner stone that the builders left out is the corner stone on which I build my church." said the Man.

  • Not quite a tiger... (Score:5, Insightful)

    by David Kennedy ( 128669 ) on Tuesday May 28, 2002 @09:39AM (#3594773) Homepage
    Couple of comments on the ever-so-brief-and-simple press release:

    (1) No mention of the increasing research into why cloning large mammals if more difficult than thought. See recent New Scientist magazines for pop coverage.

    (2) No mention of host animals. The Tiger can't be brought back whole and entire, something needs to act as a host - 90% close relative, 10% recovered DNA. Then work up.

    (3) No mention of gene pools and viable population sizes. Pick one human - clone a breeding population from them. Fancy working with them? Didn't think so.

    Still, interesting project!

    • Tassie devil (Score:3, Informative)

      by Iron Sun ( 227218 )

      No mention of host animals.

      The Tassie devil has been suggested as a host. The big advantage for the thylacine, and the reason why it will probably be the first successful recovery, is that it is a marsupial, which means it is born when it is basically still a foetus. This means that the host animal can be kept on immunosuppressants for the short duration of pregnancy without rejecting the embyo or getting too screwed up itself. Something like a mammoth, on the other hand, would need to be carried for 18 months inside what would end up being a very sick elephant.

      • Pick one human - clone a breeding population from them. Fancy working with them?

      Ooh, ooh, I pick Natalie Portman. So, yes, I do. ;-)

    • This Reuters Article [yahoo.com] answers a few of your questions.

      First, it's not a tiger, it's a marsupial with stripes (hence the Tiger moniker), related to the Tasmanian Devil.

      Second, the article talks about using a Tasmanian Devil as a potential host animal, after stripping out the genes specific to the Tasmanian Devil from the egg cell.

      It doesn't talk about gene pools or population sizes, however there are several of the animals completely preserved, and that's a LOT of genetic material to work with.

      --brian

  • Quickly collect as much sperm and eggs from endangered species as you can. If needed, try to collect these from live animals.

    If this is not possible, use cloning techniques... and try to work out the bugs of the cloning process (rapid aging, damaged genes, etc...).

    Wait until the ecological situation in the region of the endangered animal is back to normal (or as near normal as possible), "reproduce" the animal in a compatible donor, or a genetically-engineered one if no compatible donors are available. Re-introduce several cloned members of the specie. After a while, you should have restored "lost" species and ecological diversity.

    And the best thing is, you can do this even more easily with plants.

    I think this is much more interesting than freezing your own brain for posterity. Probably a much better use of genetics than GMOs...
    • That's like saying "Go ahead and fry that mission critical server, I have backups!" Sure, it'll save your ass, but its no way to run things.

      Or we could:

      a) Manage wildlife conservation at a reasonable level. (Control poaching, destruction of environment, etc).

      b) Accept that fact that species become extinct, regardless of whether by human hands or not. Why bring them back just for the sake of doing it. (See Jurassic Park for an extreme example).

      We should never mess with nature. Something as simple as introducing a new species in a different environment has caused havok around the world. (Like Zebra mussels in the great lakes). Can you imagine some genetically altered species roaming around, interbreeding and the like?

      We can't even get rid of Zebra mussels, this is an ecological nightmare waiting to happen!

  • Apologies to Blake. (Score:4, Interesting)

    by ktakki ( 64573 ) on Tuesday May 28, 2002 @09:40AM (#3594781) Homepage Journal
    Tiger, tiger, burning bright
    In the test tubes of the night,
    What immortal laborat'ry
    Could frame thy fearful symmetry?

    Sorry.

    k.

    • You're awesome! Somebody mod up the parent... and if you don't know the original poem, read it [utoronto.ca]. :)
    • "laborat'ry" should be "laborat ry'" (stress on the last syllable). Blake wrote the original in a truncate trochaic quadrameter: normally four pairs of syllables with the stress on the initial syllable, except he truncates the final pair so that each line ends on a stressed syllable, which is more natural in English verse. The last line in each verse is iambic quadrameter which further breaks up the pattern.


      Nice work, otherwise.

  • ... is cloning slashdot articles [slashdot.org]!
  • Yeah.. they made a movie about this. Anyone happen to see Juraissic Park??? Before we know it, they'll be cloning dinosaurs and raptors will take over the earth...

  • It's Not A Tiger - And It May Not Even Be Extinct! (Score:4, Informative)

    by cybrpnk2 ( 579066 ) on Tuesday May 28, 2002 @09:42AM (#3594795) Homepage
    You can find out more about "Tasmanian Tigers" at The Thylacine Museum [naturalworlds.org]. In reality it's a marsupial, not a mammal, and so it's closer to an opossum than a feline like a tiger. The only reason it's called a "tiger" is because of its stripes, as seen in the photo at the top of this webpage [pibburns.com] about mysterious animals. And it may not even be extinct [carleton.ca]...

  • A warning and a warning (Score:3, Interesting)

    by Dutchmaan ( 442553 ) on Tuesday May 28, 2002 @09:43AM (#3594799) Homepage
    For the theoligically inclined:

    Could this be classified as the dead rising from the grave...?

    For the atheologically inclined:

    The theologically inclined will be thinking this...

  • Is it really extinct? (Score:3, Interesting)

    by webword ( 82711 ) on Tuesday May 28, 2002 @09:43AM (#3594800) Homepage
    http://www.tased.edu.au/tot/fauna/tiger.html [tased.edu.au]

    "The Tasmanian Tiger , also called the Tasmanian Wolf, is a large marsupial native to Tasmania. Most scientists believe it to be extinct, however each year there are about a dozen unconfirmed sightings in remote areas of the state, and several reported sets of Tiger tracks."
  • Here's a link to the story on Yahoo!:-

    Extinct Tasmanian Tiger One Step Closer to Cloning [yahoo.com]

    Since that poor Australian server just got completely and utterly flamed... :(

  • somehow I dont think this is cloneing (Score:3, Informative)

    by johnjones ( 14274 ) on Tuesday May 28, 2002 @09:45AM (#3594808) Homepage Journal
    PCR doesnt get you a clone

    you need a host egg and the actual DNA I would like to see them synthsize it but somehow I dont think so

    regards

    john jones

  • Choosing Species (Score:2, Insightful)

    by coryboehne ( 244614 )
    It is an obvious must that any animal that would be restored using this procedure should be considered carefully, and the main critera should be based upon several points:

    1. Is the animal extinct today due to human interference?

    2. Can the animal re-establish itself in todays ecology?

    3. Is it practical to re-introduce the animal back into the wild?

    If the answer to all of these major questions (and many more minor questions) is yes, then I can see no good reason not to undo the damage humans have caused to these species.

    • You missed one (Score:4, Funny)

      by sien ( 35268 ) on Tuesday May 28, 2002 @09:48AM (#3594829) Homepage
      You left out the most important one:

      4. Does it taste good ?

    • 1. Is the animal extinct today due to human interference?
      Poison baits and modern rifles - I'd say that is a yes.
      2. Can the animal re-establish itself in todays ecology?
      It was doing OK before the poison baits and bullets, and about the only thing that has changed is that it would have to compete with a small number of foxes and some feral dogs. It would probably eat the feral cats for breakfast (as well as sheep - which is why it was made to disappear in the first place).
      3. Is it practical to re-introduce the animal back into the wild?
      That depends on how many can be produced, and political hassles like keeping them away from the sheep and small children. There's a lot of preserved specimens of these critters, including feotuses. Genetic diversity is something I don't know much about - hampsters and dog breeding broke all of the rules I've heard of about the size of a gene pool, it's more complex than X individuals to prevent inbreeding.

  • A tricky undertaking (Score:3, Insightful)

    by nucal ( 561664 ) on Tuesday May 28, 2002 @09:48AM (#3594827)
    ABC News [go.com] did a story on this last August - which provides a little more detail.

    The breakthrough here is that PCR confirmed that there was very little damage to the ethanol preserved specimen. The next step is that they are planning on using PCR amplified DNA to "rebuild" the genome of the Tasmanian Tiger. To my knowledge, all other cloning involves injecting cell nuclei into oocytes (eggs). This has the advantage of preserving genes in the proper context. This is probably not possible with the preserved specimens.

    Trying to re-build the entire Tasmanian Tiger genome, essentially from scratch, to produce artificial chromosomes is a huge undertaking - by the researcher's estimates, this could take 10-15 years.

    • The breakthrough here is that PCR confirmed that there was very little damage to the ethanol preserved specimen.

      One thing I can see happening from a full blown attempt to recreate an animal from its' DNA like this, is a vast amount of knowledge gained into the workings & preservation of dna in general - knowledge which can be put to use preserving genetic info from any species. Humans are a bit like that, we seem to work best when there's a goal, and one encompassing a wide amount of technologies like this is just the thing

      If nothing is eventually created, or a creature which became extinct 'for a reason' lives again in some form, the ability to preserve genetic information in a form that's usable in the future could be a bonus - it doesn't really seem to me like tasmania is going to be overrun by tigers in a hundred years

      a grrl & her server [danamania.com]
  • I'm capped, and yet I still whore.

    DNA, as I'm sure we all know, is double stranded. One strand is a complement of the other. A complements T and C complements G. So, if one strand is:
    5' ATTTC 3'

    then the other strand is:
    3' TAAAG 5'

    The DNA is "read" from 5' to 3'. 5' and 3' refer to particular atoms on the sugar backbone that are attached to one another via a phosphate.

    When DNA is replicated, you split it into two strands:
    5' ATTTC 3' and 5' GAAAT 3'

    (notice that the two complements read in opposite directions)

    and each strand has it's complement added.

    5' ATTTC 3' and 5' GAAAT 3'
    3' TAAAG 3' and 3' CTTTA 5'

    The problem with this is, in order for this happen to DNA, you need an RNA "primer." This primer is a complement to the beggining of what you want to replicate. So, for example, if you have (RNA bases I'm putting in bold. U is the same as T:)

    UAA

    floating around in solution, which compliments ATT, then any sequence beggining with ATT will be replicated, but other sequences will NOT be replicated, because no RNA primer is available to get them started.

    So, if you have a whole mess of DNA, including a piece that you're interested in, which reads:

    5' ATTTG (long space........) TCGTC 3'
    3' TAAAC (long space........) AGGAG 5'

    and you add:
    TAAAC and TCGTC

    You get a chain reaction; the sequence flanked by the complements of the two things you add (the sequence printed above) is replicated, and then the replication product is replicated, and so on and so on. Other sequences, which are flanked by only one compliment (only ATTTG, say) will be replicated occasionally, but there replication products cannot in turn replicate, so you get no chain reaction.

    More history here [berkeley.edu].

    A thermophile (heat loving organism), thermus aquaticus, provided a polymerase [whyfiles.org] (an enzyme which polymerises, that is to say replicates sequences of, nucleic acids like DNA and RNA) that works extremely fast at high temperatures. In general, the higher the temperature you run a reaction at, the faster it goes. However, most biological enzymes (from, say, a person) cease to function when temperatures rise (this is one of the ways heat kills you.) Thermophiles, bacteria that live in geysers and in volcanic ocean vents, have evolved enzymes that continue to function at higher temperatures.
    • So....

      If CTAATGT binds to GATTACA, then what happens when you throw an invalid U-gene into the mix?

      Hint: all this craziness leads to the eventual demise of Law.

    • Why RNA? (Score:2, Informative)

      by Apogee ( 134480 )
      Where did you get this RNA primer stuff from?

      I believe that's how it was done, back when PCR was invented (back in 1985 or so) but nowadays, no one uses RNA as primers without a very good reason to do so. Why? RNA is unstable, and you have RNAses (enzymes that break up RNA) on your hands, in your spit, everywhere ...

      What's used today is short oligonucleotides as primers. These are short, single-stranded DNA stretches that are synthesized by a chemical process and subsequently purified. They are available from commercial suppliers at something like 50 cent a base.
    • 5' ATTTC 3'

      5' ATTTC 3' and 5' GAAAT 3'
      5' ATTTG (long space........) TCGTC 3'
      3' TAAAC (long space........) AGGAG 5'

      Yes Alex, I'd like to buy a vowel...

  • Also see SMH (Score:3, Informative)

    by gagravarr ( 148765 ) on Tuesday May 28, 2002 @09:59AM (#3594891) Homepage
    The Sydney Morning Herald [smh.com.au] have just done an article [smh.com.au] on this. While it doesn't cover much more than the one linked in the article, it has links to some other SMH articles. One Of them [smh.com.au] is an interview with one of the main scientists behind it, and is quite insightful. The other is a gallery of relevent photos.
  • From the article, "In 1999 DNA was successfully extracted from an ethanol preserved Tasmanian Tiger pup sample."

    So... that would be beer-battered Tasmanian Tiger pup? Mmmm good!

  • Everyone knows it's gonna happen. Someday, these scientists are gonna create a breed of killer tomatoes!!! It will be the end of the world as we know it...
  • What's to stop them from cloning Elvis? It has to stop somewhere. Although the idea of cloning Jesus Christ does sound pretty cool. But I think God would be pissed and just end the world right there and then.

  • Couple More Species (Score:5, Interesting)

    by 4of12 ( 97621 ) on Tuesday May 28, 2002 @10:19AM (#3595008) Homepage Journal

    I'd sure like it if a couple of species would return to existence that were obliterated earlier.

    Two examples from the last several hundred years include the great auk and the passenger pigeon.

    Two examples of species that humankind hunted to extinction (since they were such wonderful food sources) include the woolly mammoth and the giant sloth.

    I recall an historical account of the last great auk being killed so that it could be stuffed and placed in the British museum. The collectors also took pains to destroy the last eggs in the nest at the same time. Gives you some idea of how much our views of what is fitting and proper for us to do in the world can change over a few hundred years.

    Now that there are so many of us humans in a finite sized world, and our technological means of changing the world are more influential, it behoves us to give more and more thought to the consequences of our actions.

    It's really only our capability for reasoning and thought that gives us a chance of beating the other animals for long term survival of our species.

  • PCR is a technique that is successful in replicating even very small pieces of DNA. It 'amplifies' extremely small samples of material into amounts that are detectable. Essentially, this group in Australia has determined that they have some DNA from the Tasmanian Tiger, but they have no idea how much of the genome. It is highly likely that there just isn't enough enact DNA to be useful for the creation of an animal.
    Assume for a moment that they are exceptionally lucky and have an intact genome from two individuals, one male and one female. The scientists then pass the substantial hurdle of cloning these individuals (no marsupials have been cloned yet). What do they have: two individuals. This would amount to a 'population bottleneck' of the worst magnitude. Who will these animals' offspring mate with?
  • I've been reading the late Stephen Jay Gould's book Dinosaur in a Haystack, in which he notes that Jurassic Park-style cloning wouldn't work for a number of basic technical reasons.

    Did he ever mention this project in any of his other books? DiaH is the only book I've read so far...
  • Species die out, new species evolve.

    Attempting to stop time and preserve all existing species at a specific point in time is a truly futile act.

  • Whatever happened to that wooly mammoth that was excavated from a frozen lake in the arctic a couple years ago. It was a big deal on the Discovery channel.

    Anyways, I remember them saying they were going to try to extract some DNA from the beast and then close it. Anybody have any information on that project?
  • It does a good thing to the nature we are and been a part of and breaks the boundary of our existential level.

    Creating remote controlled animals [economist.com] and therefore taking away what them BE, should account for more concern.

  • No one seems to have mentioned the biggest hurdles in cloning an extinct mammal.

    Sure you can amplify bits of DNA from the thylacine (aka Tasmanian tiger).

    You might be able to reconstruct the entire genome, or at least reconstruct the coding part of it exactly and the non-coding parts of it (like junk DNA) closely enough to work.

    But you still have two hurdles:

    • You need to make the genome into functioning chromosomes. This means wrapping huge DNA molecules with a structural scaffolding of protein and stuff. There are also chemical modifications to some bases (such as methylation) which occur in poorly understood patterns and affect gene expression. Artificial chromosomes have been made, but I don't think we know how to assemble a stable, full-size, fully functioning chromosome yet.
    • More importantly, say you have total genome sequence assembled into chromosomes - what do you do with it? To produce an animal, you also need to reconstruct a thylacine ovum (egg). A mammal's ovum is full of special genetic instructions (mRNA) and regulatory proteins produced by the mother. How will we make one? Even if we found a preserved one, nobody knows how to assemble a functioning animal cell, let alone one of an unknown type. I seriously doubt the Jurassic Park solution of "use an egg cell from a related species" would work.
    To really clone an extinct animal, you'd need to have to reconstruct how the ovum worked by some kind of fantastically complex computer simulation based on the genome sequence. Then you'd have to make the ovum, put it in an artificial womb or modern day host (which would be fairly easy compared with the previous bits), and bring it to term.

    I think any information we can get about the thylacine is worth getting, but don't hold your breath for results ...

  • As others have correctly pointed out, this isn't cloning. they are taking the genes of an organism and assembling them on an "artificial" chromosome.

    The technology to do this is really in its infancy. Few other, if any, organisms have been prepared this way (to my knowledge), including the lowly bacteria (several orders of magnitude easier). The only research I know of that really has had success is the reduction of E.coli genome as published recently in Genome Research.

    I highly doubt that we understand the marsupial genome enough to assemble it together in a way that will "work" (an enormous project by itself). This all has to be performed before the difficult cloning event (cloning the "artificial" genome into another working host cell).

    While I believe the technology will be available, it will be a long time before we actually see this projects completion. To get there it is going to require a lot of grunt work. And unlike programming, bugs will be *very* difficult to weed out. If it doesn't work it might be because gene #1 and gene #23,423 aren't next to each other. How would you find this out? I applaud the effort, but I think we need to have a model of this technology on a simpler organism (not extinct) before anyone should spend crap loads of $$$ on a potential dead end.

    -Sean

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