Furry Mice: A Step Toward Bringing Back Woolly Mammoths

Scientists have made a big leap in bringing back the woolly mammoth. They have created mice with thick, woolly fur, similar to what woolly mammoths had. This fur helped the mammoths survive the cold during the last Ice Age. The scientists used advanced genetic engineering techniques to modify specific genes in mice. These genes control hair texture, length, and density. The result? Mice with long, wavy, and dense fur, just like a woolly mammoth's coat. The project started less than a year ago. Researchers quickly designed and cloned genetically modified mice to test if mammoth-like traits could be reproduced. The findings were shared on March 4, 2025, on a preprint database. This marks a big step in efforts to bring back the woolly mammoth. The scientists didn't directly use mammoth DNA. Instead, they found mouse genes that are similar to those in mammoths. They then made multiple changes to these genes. One key change involved blocking a gene called FGF-5, which controls hair length. This resulted in mice with fur three times longer than normal. The researchers also altered two other genes, TGF alpha and KRT27, which affect hair waviness and thickness. This produced mice with long, wavy fur, showing that multiple genetic changes can create mammoth-like traits. Using mice as a test model is a crucial step. Mice have a quick reproductive cycle, allowing researchers to test and observe genetic changes rapidly. This is much faster than waiting years to see changes in larger mammals like elephants. The lessons from these mouse experiments will be applied to editing elephant cells, which is a much more complex process. However, applying these techniques to Asian elephants presents significant challenges. Elephants have sparser hair than mice, so even with the same genetic modifications, the resulting coat may not be as dense or insulating as a mammoth's. Additionally, modifying elephant embryos is far more complex due to their long gestation periods and the need for advanced reproductive technologies. The next step for the scientists is to test if the woolly mice can tolerate cold temperatures better than standard mice. If the woolly mice prove to have enhanced resistance to cold, it would further validate the feasibility of introducing similar adaptations in elephants. Despite the challenges, the project is moving forward. The ultimate goal is to produce the first woolly mammoth hybrid calves by 2028. If successful, these hybrids could be reintroduced into Arctic habitats. There, they could help restore grassland ecosystems and combat climate change by preventing permafrost thaw. The woolly mice experiment is just one small step in a much larger process, but it represents a major milestone in the quest to bring back the woolly mammoth.