Can the woolly mammoth really be resurrected? Scientists are one small step closer

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A bold plan to genetically engineer a version Woolly MammothAn ice age giant that disappeared 4,000 years ago is making some progress, according to concerned scientists.

The long-term goal is to create a living, walking elephant-mammoth hybrid that is visually indistinguishable from its extinct predecessor.

Resurrecting endangered species has been a pet project of Harvard University geneticist George Church for more than a decade. In February 2021, Church joined Dallas-based Colossal Biosciences with entrepreneur Ben Lamm, and the project gained traction later that year with an infusion of cash and the glare of publicity.

Many challenging tasks still remain, such as creating an artificial womb capable of delivering baby elephants. But Colossal Bioscience said Wednesday it has taken a “significant step” forward.

Church and Colossal's head of biological sciences, Eriona Hysolli, revealed that cells from a close relative of the mammoth, the Asian elephant, had been transplanted into the embryonic stage – a first. Stem cells are derived from elephant cells. The team plans to publish the work in a scientific journal, but the research has yet to undergo peer review.

These modified cells, called induced pluripotent stem cells, or iPSCs, can be further teased out in the lab and grow into any type of elephant cell — an important tool for researchers to model, test and refine the genetic changes they need to make. Give the Asian elephant the genetic traits it needs to survive in the Arctic. These include a woolly coat, an insulating layer of fat, and small ears.

“So the beautiful thing about cells is that they can renew themselves indefinitely and differentiate into any type of cell in the body,” said Hysolli, the institute's lead scientist on the massive project.

Stem cells could make it easier for conservation scientists to study the Asian elephant's unique biology. For their size, the organisms are uniquely resistant to cancer—for reasons that are not well understood. A major hurdle for the team in developing the elephant cell lines was blocking genes thought to confer cancer resistance.

Cellular research techniques pioneered by Colossal have opened up a new way to save endangered elephants, said Oliver Ryder, director of conservation genetics at the San Diego Zoo Wildlife Alliance.

“The idea of ​​making iPSCs from elephants has been around for years. It's been difficult to accomplish,” said Ryder, who was not involved in the research. “The impact on conservation will be in gene recovery and assisted reproduction,” he added.

For obvious reasons, naturally occurring elephant embryos are difficult to study. The stem cells will allow scientists to model elephant embryos, raising the curtain on how an elephant develops into a fetus — a “very valuable asset,” Ryder said.

Elephant stem cells also hold the key to mammoth regeneration. Once edited to have mammoth-like genetic traits, the elephant's cells could be used to create eggs and sperm and an embryo that could be implanted in a kind of artificial womb. However, it will work for many years.

The beginning is given The team plans to first use the cloning techniques used in 1996, the six-year deadline set by Colossal. Dolly Goat, inserting genetically modified cells into a donor egg fertilized by a surrogate mother elephant. However, even though that technology has been around for a while, the results have not been successful. Many question whether its use is ethical Given the potential for failed attempts, endangered animals are surrogate mothers.

“I think the first recorded elephant will be a major milestone, probably six years from 2021, consistent with Ben (Lam's) prediction,” Church said. “The second thing that makes us happy is that we have something that's resistant to cold. And then the third thing is if we can do it in a scalable way that doesn't involve surrogates. That's the unknown,” Church said.

The research team at Colossal has already analyzed the genomes of 53 woolly mammoths from ancient DNA recovered from fossils. A wide range of samples from animals that lived in different places in the past helped scientists understand which genes make a mammoth unique.

“We've come a long way. Mammoth DNA quality is as good as elephant, both are almost as good as (DNA extracted from) humans,” Church said.

Church and Hysoli did not say exactly how many genetic changes would have to be made to the Asian elephant's DNA to create a mammoth-like creature capable of withstanding arctic temperatures. Geneticists also want to design a mammoth without tusks, so the animals don't fall prey to predators.

The Church was at the forefront of the work Genetically engineer pigs He said up to 69 revisions can be made simultaneously in pigs, with organs compatible with the human body for transplant. He said the number of changes needed to make an Asian elephant cold-tolerant would be broadly similar.

Colossal longed that mammoths, if they returned in sufficient numbers to the grasslands of the northern part of the planet, would help slow the thawing of the permafrost.

Some scientists believe that before their extinction, grazing animals such as mammoths, horses, and bison trampled grasslands, felled trees, and compacted snow to freeze the earth beneath.

One Small study Published in 2020, it suggested that the presence of large mammals such as horses, bison, yak and reindeer in Siberia results in lower soil temperatures in the protected area compared to land outside the boundary. Still, it's hard to imagine herds of cold-blooded elephants having a significant impact in a region that's warming faster than anywhere else in the world. Other experts have said.

Colossal announced plans for a revival Tasmanian tiger in 2022 and Dodo in 2023, but Mammoth's work has been a long time coming.