What? Is this a joke, Ethan? Have you been watching Jurassic Park again, drinking Dino DNA or something? No, I got an interesting question from startswithabang.com reader and ichthyophobe Lucas:
Over the years a few intact, frozen woolly mammoth have been found and procured by different scientists and governments, most recently Japan. What are they doing with these ancient popsicles? Cloning? Could a frozen woolly mammoth be effectively cloned?
Aaah, the woolly mammoth, something we think of as ancient, but really it only went extinct an estimated 3,700 years ago, with the last mammoths dying on Wrangel Island in Northern Russia. Because we’ve found so many carcasses of woolly mammoths in Siberia and Alaska, we know what they looked like very accurately:
(Apparently, they largely ignored their human predators on the left, and that’s why they’re extinct.) So we’ve got the frozen ones, some (bizarre) scientists are thawing them, and Lucas isn’t crazy, people have been speculating about how to clone them.
If I wanted to clone it, though, what would I need? Well, in the end, you still need a fertilized woolly mammoth egg. This needs three components:
- An intact egg.
- Complete woolly mammoth DNA.
- A fertilized, ready-to-reproduce nucleus.
Well, the first one is easy. You can do it the hard way, which is to thaw a female woolly mammoth and find an intact egg in her ovaries that hasn’t sustained any damage from being slowly frozen after already being dead and decaying. Umm… that sounds pretty preposterous, doesn’t it? But like I said, getting an intact egg is easy. Because you can use an elephant egg. Did you know you can mix eggs like that? Well it’s been done already, a cow has given birth to a live bison, and a human nucleus has been infused into a cow’s egg, and divided just like a fertilized egg! How does this happen? It turns out that, nuclei aside, almost all mammalian eggs are pretty much identical. So that’s step one taken care of, just by getting an elephant.
So now you’ve got your egg. What to do next? Well, I think that’s pretty clear: you’ve got to get it fertilized. You can try it old-school (regular old egg+sperm), or new-school (above). The old-school drawback is that we’d need an intact woolly mammoth egg with intact DNA and intact woolly mammoth sperm. You’re not likely to hit the jackpot twice. Artificially implanting a “naked” host egg cell (elephant egg with the nucleus removed) with woolly mammoth DNA isn’t enough, either. Although we need complete mammoth DNA, and that’s hard to get, because dying, decaying, and getting frozen tends to damage DNA (and for an incomprehensible technical explanation, see here), even getting that wouldn’t be enough. You need complete DNA inside a preserved and undamaged nucleus. In fact, what scientists have found here is that an undamaged nucleus in a damaged cell will often be fine, but a damaged nucleus in an undamaged cell is doomed.
So what do we do? Well, in living organisms, the place to go for undamaged cell nuclei is into the bone marrow. Could this be where woolly mammoths have their best chance for undamaged DNA? I have no idea. What they’re going to have to do is search that whole damned carcass looking for an intact nucleus full of good, healthy mammoth DNA. Then you stick your junk in that egg, and that’s the way you do it.
So what are the prospects for this? Well, from this report, you can try the following as your best bet:
If they can get an intact cell nucleus, they may try to clone the mammoth using an elephant egg and an elephant as a surrogate mother. Or they might use frozen sperm, if they can get any, to try to create an elephant-mammoth hybrid.
So if they get an intact nucleus, they’ll do what I said above, but that second possibility isn’t exactly what Lucas wanted, but damn, is that interesting! Could we even do that — make a woollephant? We don’t know whether woolly mammoths and elephants can breed, whether they’re the same species, or whether their offspring would be viable (or as sterile as mules), but what an interesting possibility!
Thanks, Lucas, for making me learn all this weird stuff to answer your question. Got comments? Got questions? You know you do… ask ’em here. I’ve got plenty to get to, but more are always welcome!