What The Woolly Mammoth De-Extinction Project Actually Means


Sarah Hedgecock, Forbes

Date Published

See link for photo & video.

If you’ve been following genetics news in the past few weeks, you’ve probably seen the headlines: “Woolly mammoth will be back from extinction within two years, say Harvard scientists”! “Woolly mammoth on verge of resurrection, scientists reveal”! Is the de-extinction hype real? Well, sort of.

A group of scientists led by renowned geneticist George Church is, indeed, working on creating a mammoth of sorts. But it’s not quite a mammoth. It’s probably more than two years away. And it’s going to be really expensive.

“You want me to throw a number at you, maybe a billion dollars,” says Rob DeSalle, Ph.D., a geneticist and the curator of molecular systematics at the American Museum of Natural History in New York City. “Putting that much money into resurrecting one species really seems to me to be misguided.” Ross MacPhee, Ph.D., curator of the museum’s department of mammalogy, puts the total cost of such a project at approximately “a zillion dollars.”

“It’s not enough to bring them back,” says Ross. “You have consideration of what are you going to do with them.”

But first, the woolly mammoth genome must be sequenced (at “huge cost,” according to DeSalle). So must the Asian elephant genome: rather than truly bringing back a mammoth, Church is working on editing elephant genes to reflect a mammoth’s phenotypic traits, like long hair and extra subcutaneous fat. Says DeSalle, “It’s not really a clone and it’s not really an elephant and it’s not really a mammoth. A mammophant?”

Once both genomes have been sequenced, the modified genome must be injected into an Asian elephant egg. So far, Church’s lab has made 45 mammoth-like edits to the elephant genome, but there would be a lot more required to move the resulting embryo into true mammophant territory.

If anything is going to happen within two years, it will probably be that embryo. The costs–and time-only keep going up after the egg is implanted in an elephant uterus. Elephants give birth one at a time, after a 22-month pregnancy. Putting aside any potential issues with the viability of a mammophant embryo (of which there are a lot), that’s a really long time to wait to see if a single data point is going to work out, and some of the mammoth-like traits might not even be apparent right away. To get around this, Church has proposed using artificial wombs. There’s one problem: not only would the costs of building a working artificial womb good enough to spend 22 months growing a 200-pound organism, but if it succeeded, that would probably be bigger news than the mammophant itself.

Further problems and costs arise once we have a living, breathing newborn mammophant. The monetary and ethical issues don’t stop once the concept has been proven, MacPhee explains. “The only kind of comparable situation we have is importing wild beasts from Africa or Asia to this country, and where do they go? They go to zoos, they go to game parks, which just makes them hothouse plants. They’re not really being reintegrated.” It’s not quite the de-extinction trumpeted by the headlines.

“Under these circumstances, can we expect woolly mammoths by the end of the decade?” asks MacPhee. “I’m much more dubious about that, but I know that Church and his colleagues are very keen to show that this can be done.”

So get excited about the work. But remember: this is just basic research proof of concept right now. You won’t be riding a mammoth to work by 2020.