Colossal Biosciences engineers genetically modified mice with woolly hair, marking a step toward recreating traits of the extinct woolly mammoth using CRISPR technology.
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| Colossal Biosciences' new genetically modified "woolly mice" feature thick hair, part of a larger initiative to bring woolly mammoth traits back using gene editing. Image: ChicHue |
Dallas, USA — March 5, 2025:
Colossal Biosciences, a biotech company aiming to bring extinct species back to life, has achieved a significant breakthrough by genetically engineering mice with thick, woolly hair. This development marks a key step toward recreating traits of the woolly mammoth, an extinct species that once roamed the Earth’s frozen tundras.
Using CRISPR gene-editing technology, scientists at Colossal edited seven genes in mouse embryos, resulting in rodents with hair similar to that of the long-extinct mammoth. The company has coined the term "Colossal woolly mouse" for these newly modified creatures. While the results were shared publicly, they have yet to be peer-reviewed or published in a scientific journal.
“It’s technologically impressive,” said Vincent Lynch, a biologist from the University of Buffalo who was not involved in the study. Scientists have been genetically engineering mice for decades, but modern tools like CRISPR make the process more efficient.
Beth Shapiro, Colossal’s chief scientist, explained that the genes selected for this project were linked to cold tolerance and fat metabolism, traits that would have been essential for woolly mammoths’ survival on the Arctic steppe. These genetic mutations are already present in some living mice but were combined in one creature to replicate the mammoth’s survival traits.
While the company’s focus is currently on mice to test the process, Colossal intends to use this method to eventually edit the embryos of Asian elephants, the woolly mammoth’s closest living relatives. However, ethical concerns and the endangered status of Asian elephants mean that significant hurdles remain before this research can advance.
Despite Colossal’s progress, many independent scientists remain skeptical about the idea of “de-extinction.” Critics, like Christopher Preston from the University of Montana, argue that altering an Asian elephant’s traits doesn’t equate to resurrecting a woolly mammoth.
Nonetheless, the success of gene-editing mice could have broader implications for conservation and animal agriculture, offering potential new approaches to preserving species or improving livestock. Bhanu Telugu, an expert in animal biotechnology at the University of Missouri, praised Colossal’s innovative methods for targeting specific genes.
Beyond its ambitious plans in biotechnology, Colossal also envisions applying these techniques to human health, with Lamm noting that the company has spun off two healthcare startups focused on disease prevention and gene therapy.
“It’s part of how we monetize our business,” Lamm said, highlighting the company’s future in both biotechnology and healthcare innovation.