Woolly Mouse: Mammoth De-Extinction

• Colossal Biosciences has created a "woolly mouse" as a step toward resurrecting the extinct woolly mammoth.
• The woolly mouse has shaggy, mammoth-like fur and cold-adapted traits.

Development of the Woolly Mouse

• Researchers sequenced ancient mammoth DNA to identify genes controlling traits like coat color and cold tolerance.
• Corresponding genes in lab mice were altered, along with other modifications to the rodents’ genome.
• The purpose is to tweak DNA in existing species to make them more resilient, and to help the environment.
• Colossal claims mammoths could help fight climate change by tamping down Arctic permafrost and reducing methane release.
• Colossal’s CEO Ben Lamm questions, “Why leave nature to chance?” regarding their approach.
• Colossal has raised hundreds of millions of dollars from investors for their "de-extinction" goals.

Skepticism and Concerns

• Experts are skeptical about rewilding due to potential conflicts with humans and vulnerability to predators.
• Concerns exist about the unknown consequences of releasing a mammoth or elephant-mammoth hybrid.
• Paleontologist Elsa Panciroli believes gene editing misses the bigger picture of habitat loss, human conflict, and climate change.

Colossal's Process and Claims

• Colossal was co-founded in 2021 by Ben Lamm and Harvard biologist George Church.
• They created elephant stem cells in 2024, vital for conservation breeding programs and cloning future hybrids.
• Chief Science Officer Beth Shapiro sees the woolly mouse as validating their approach to resurrecting lost traits.
• The team targeted genes in mouse genomes to create mammoth-like hairs, patterns, and color.
• They altered hair texture using a mammoth gene variant (allele) affecting keratin.
• Lipid metabolism was also targeted to develop cold-adapted elephant-mammoth hybrids.

Ethical Implications and Potential Hazards

• Bioethicist Robert Klitzman questions the value of the woolly mouse beyond its "wow" factor, citing gene editing's high failure rate.
• Shapiro states that all mice born are still alive and under the full-time care of veterinary staff.
• Concerns exist about the potential biological implications if a mouse escapes the lab and mates with wild populations.
• Geneticist Jiangbing Zhou expresses concern about the potential risks as the function of ancient DNA in live mice may be unpredictable.
• Shapiro says genetic changes are not a cause for concern although more caution is necessary when selecting genetic variation.
• All engineered mice born so far are male and will not be bred.

Perspectives on De-Extinction

• Andrea Crosta points out reintroduced animals are routinely targeted by poachers.
• Philosophy professor Craig Callender believes the woolly mouse could be a great tool for genetic engineering.
• Callender considers the mammoth project a "stunt" without inherent value.
• Shapiro says their work inspires future scientists and promotes hope about the future.
• Shapiro believes gene editing can be used alongside traditional conservation approaches.
• Sue Lieberman considers the project a waste of money when conservation is underfunded.
• Biologist George Schaller emphasizes the need to protect what we have.