If you watch or read the news, you can hardly avoid the newest hype about the “de-extinction” of the woolly mammoth (Mammuthus primigenius)—hype that implies that scientists, using genetic engineering, are on the verge of bringing back that extinct pachyderm. (The species, which coexisted with humans, went extinct about 4,000 years ago, when the Egyptians were still thriving.)
Yes, in a Jurassic-Parkish gambit, scientists are proposing to bring the mammoths back: to “de-extinct” them. A company called Colossal Biosciences, with George Church as its founder, proposes to give us woolly mammoths again, and may even allow us to fill the tundra-steppes of Eurasia with a species that no longer lives there.
It’s not true. They are not producing real woolly mammoths, and the program will not succeed even if they produce the faux mammoths they’re trying to make.
In my previous post on this, called “a mammoth debacle,” I pointed out a number of problems with this effort, not the least the misrepresentation by the media (encouraged, I think, by the scientists) that they really were going to bring back the species that had gone extinct. This is not true—not even close.
What they are going to do is put a handful of mammoth genes (we have the mammoth DNA sequence since we have individuals dug out of the permafrost) into an elephant genome, producing, so the company hopes, a large, hairy elephant with tusks. In other words, the animal they propose to produce is simply an elephant with a few mammoth genes that makes it look superficially like a mammoth. One problem is that we don’t know exactly which genes produce these traits in the mammoth; all we have are DNA sequences. We can investigate what the genes do, but putting them in an elephant genome via CRISPR and hoping that the result will look like a mammoth, is an expensive process, and likely to fail. And you don’t get many chances to fail, because each time you do this you need a female elephant in heat that you can impregnate with a genetically modified elephant egg.
But wait! The problems are much greater than this! Here’s what I wrote last time:
Further, a lot of other genes differ between a mammoth and an Asian elephant. What guarantee is there that the inserted mammoth genes would be expressed correctly, or even work at all in concert with the Asian elephant developmental system?
But it gets worse. Since you can’t implant a transgenic embryo into an elephant mom (we don’t know how to do that, and we would get just one or two chances), Church had this bright idea:
Initially, Dr. Church envisioned implanting embryos into surrogate female elephants. But he eventually soured on the idea. Even if he could figure out in vitro fertilization for elephants — which no one has done before — building a herd would be impractical, since he would need so many surrogates.
Instead, Dr. Church decided to make an artificial mammoth uterus lined with uterine tissue grown from stem cells. “I’m not making a bold prediction this is going to be easy,” he said. “But everything up to this point has been relatively easy. Every tissue we’ve gone after, we’ve been able to get a recipe for.”
An artificial mammoth uterus? Seriously? If you think that’s gonna work, I have some land in Florida I’d like to sell you. Of course, if you’re going to breed these things, you’d have to make two of them of opposite sexes. Could they even do that?
I haven’t even mentioned the ecological problems. Mammoths no doubt had cold-tolerance genes and behavioral genes for existing on the northern tundra-steppes and tending baby mammoths. How are they going to find those genes?
Now the Washington Post tells us (and everybody else) that Colossal Biosciences is “close” to producing this mammoth, which is really a big hairy elephant. But they don’t say that in the headlines. But at least the Post mentions some of the problems with this doomed effort, quoting scientists who are dubious about the venture. And, luckily, those scientists include our own Matthew Cobb.
But the bottom line is: NO, they are not going to bring back the woolly mammoth, nor will they bring the species back as a going concern.
Click below to read, or find the article archived here.
Quotes from the paper are indented. The big news is that the company is now able to get elephant stem cells that they can genetically engineer, making them a bit mammothier. These genetically engineered cells are then to be injected into a female elephant when she is in estrus. The news, as Matthew told me (he’s quoted in the piece), is that “they are able to fiddle around with elephant stem cells for the first time.” But again, this that just allows production of a big hairy elephant with tusks.
But I digress. From the piece:
“It’s probably the most significant thing so far in the project,” said George Church, a Harvard geneticist and Colossal co-founder. “There are many steps in the future.”
For proponents, bringing back vanished animals is a chance to correct humanity’s role in the ongoing extinction crisis. Breakthroughs in their field, they say, may yield benefits for animals still with us, including endangered elephants.
Yet the technical challenges of birthing into the world a living, breathing mammoth remain, well, colossal. And the project raises hairy ethical questions: Who decides what comes back? Where will the reborn species go? Could the money be better spent elsewhere? And how hard will “de-extinction,” as the revival efforts are known, be on the animals themselves?
And the BIG NEWS:
Scientists have produced such stem cells in the lab for other animals, including humans, mice, pigs and even rhinos. But for years, getting the right elephant stem cells to test all those cold-climate characteristics proved elusive, in part because elephant cells’ ability to avoid cancer made reprogramming them difficult.
Colossal said they have produced the stem cells they need by suppressing the anti-cancer genes and bathing the cells in the right chemical cocktail. Colossal published a preprint Wednesday that is not yet peer-reviewed. The company said it is working to place the study in a peer-reviewed scientific journal.
I’m curious how they’re going to test whether a given gene, beyond producing hair, increases cold-tolerance.
Further, Matthew and I are both concerned with the ethical questions, especially bringing into being a mammothy elephant not designed to survive on the tundra, and then putting it in that habitat. It has no mate, it doesn’t have the genes for surviving on the tundra, and it will likely die. If scientists ever screw up by “playing God,” well, this may be one example.
Here’s Matthew and another biologist expressing doubt about the whole mishigass:
Matthew Cobb, a zoologist at the University of Manchester in England, said all those “ifs” may be insurmountable. There is no guarantee that the modified chromosomes can be introduced to an elephant cell, or if that an embryo will take hold in an elephant womb.
And perhaps more profoundly, there is the question of how a mammoth, if born, will learn to behave like a mammoth. “Most of the mammals and birds that are being talked about have complex social and cultural interactions that have been lost,” Cobb said. “They are not simply their genes.”
Modern elephants, for instance, are highly social beings, passing down knowledge about the location of watering holes and other survival skills from one generation to the next. Their ancient cousins may be similar. “They’ve got no elders to raise them, to teach them,” Browning said. “They’re got no way of learning how to be mammoths.”
And any living surrogate elephant meant to gestate and give birth to a new mammoth will go through some degree of hardship. “How many dead elephants are we willing to have to get one woolly one?” said Tori Herridge, a paleobiologist specializing in ancient elephants at the University of Sheffield in England.
Finally, there’s the artificial uterus problem. Last night the NBC News said a woolly mammoth could be only five years away. Don’t you believe it! Here’s Church touting not only bringing back the mammoth, but trumpeting (pardon the pun) the idea that this complicated technology could help save modern species of elephants (there are three: two species of African elephant and the Asian elephant):
Colossal said its long-term goal is to use artificial wombs to gestate the animals, itself a tall technological task. The company notes that its research into elephant cells can help with current conservation efforts, such as potential treatments for a form of herpes that kills young elephants. Indeed, the company hopes to make money by licensing or selling some of the technologies it creates along the way.
“It’s not so much bringing back the mammoth, it’s saving an endangered species,” Church said. “It’s working out technology that’s useful for conservation and climate change.”
But Cobb said the biggest threats facing elephants are hunting, habitat destruction and other conflicts with humans, adding: “How will a greater understanding of cell biology help?”
Ceiling Cat bless Dr. Cobb for fighting the hype that creeps into science reporting!
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A satirical article that appeared in Clickhole (h/t: RM). Click to read:
