How Colossal’s Woolly Mouse Is Proving the Science Behind Mammoth Revival

In this OK! Magazine feature, the spotlight turns to Colossal Biosciences’ woolly mouse, a genetically engineered rodent with traits borrowed from the extinct woolly mammoth. The mice, dubbed Colossal’s “Woolly Mouse,” sport golden, wavy fur and upgraded fat metabolism—key adaptations to cold environments. Created by editing seven mammoth-associated genes via CRISPR in mice embryos, the experiment validated Colossal’s full de-extinction pipeline on a fast and manageable model organism. Beyond the science, the viral imagery of these tiny, woolly creatures has ignited public curiosity—especially among kids—introducing new audiences to genetic engineering and conservation biology. While not the mammoth itself, the project marks a major milestone: proving that complex ancient traits can be re‑expressed in living models, and laying the groundwork for future work with larger species.