Scientists Genetically Engineer World’s First Woolly Mouse to Aid Mammoth De-Extinction Efforts

Scientists Engineer ‘Woolly Mice’ Using Mammoth DNA, a Step Toward De-Extinction
[Image: Woolly mouse (left) with thick, curly fur compared to a regular mouse (right). Caption: Engineered mice show traits inspired by woolly mammoth DNA.]

In a novel step toward resurrecting the woolly mammoth, Colossal Biosciences has created the first genetically engineered mice with mammoth-like traits. These “woolly mice” boast thicker, curlier fur—achieved by editing eight key genes linked to cold adaptation in ancient mammoths. While small, this breakthrough validates methods that could someday help revive extinct species.

The Science Behind the Mice
By comparing woolly mammoth DNA with that of modern Asian elephants (which share 95% of their genome), researchers pinpointed genes tied to survival in icy climates. These include traits like hair length, texture, fat storage, and coat color. Using CRISPR and other tools, the team edited fertilized mouse embryos, implanting them into surrogate mothers.

Key genetic tweaks:

• FGF5 gene modification: Led to hair three times longer than normal.
• Lipid metabolism genes: Could aid fat storage for insulation.
• Coat changes: Lighter color and curlier texture similar to mammoths.

[Image: Close-up of woolly mouse fur. Caption: Edited genes replicate mammoth-like adaptations for cold climates.]

From Mice to Mammoths
Colossal aims to apply this approach to elephants, creating hybrid mammoth-elephants capable of thriving in Arctic regions. The goal is to produce embryos by 2026 and calves by 2028. These hybrids could potentially rewild ecosystems, possibly slowing permafrost melt by trampling snow and promoting grass growth.

Challenges & Criticism
Despite progress, hurdles remain:

• Gestation: Elephant pregnancies last 22 months, with calves maturing slowly.
• Ethics: Manipulating endangered elephants raises welfare concerns.
• Ecosystem impact: Unclear how reintroducing mammoths would affect modern environments.

Critics argue editing mice isn’t proof for elephants. Dr. Alena Pance (University of Hertfordshire) notes the edits merely deactivate genes rather than fully “resurrecting” mammoth DNA. Others, like Dr. Denis Headon (University of Edinburgh), stress that fur alone won’t equip elephants for Arctic survival.

[Image: Artist’s impression of woolly mammoths in Arctic. Caption: Colossal envisions herds reshaping tundra ecosystems.]

Looking Ahead
Colossal acknowledges the uncertainties but emphasizes rigorous testing. As CEO Ben Lamm states, “The mouse model provides a fast, ethical way to test gene traits.” While de-extinction remains contentious, these fluffy mice mark a intriguing milestone in merging ancient genetics with modern science.

Woolly Mammoths: Key Facts

• Habitat: Roamed Eurasia and North America during the Ice Age.
• Traits: Thick fur, curved tusks up to 16 ft, and small ears to retain heat.
• Extinction: Disappeared ~10,000 years ago due to climate shifts and human hunting.
• Significance: 99.4% genetically identical to modern Asian elephants.

[Image: Mammoth skeleton vs. elephant. Caption: Mammoths diverged from elephants 6 million years ago.]

While woolly mammoths won’t roam tomorrow, Colossal’s work sparks debate on science’s role in reshaping nature—one gene at a time.