Rachel Haurwitz quickly went from lab rat to CEO at the center of the frenzy over CRISPR, the breakthrough gene-editing technology. In 2012 she’d been working at Jennifer Doudna’s lab at the University of California, Berkeley, when it made a breakthrough showing how to edit any DNA strand using CRISPR. Weeks later, Haurwitz traded the lab’s top-floor views of San Francisco Bay for a sub-basement office with no cell coverage and one desk. There she became CEO of Caribou Biosciences, a spinout that has licensed Berkeley’s CRISPR patents and has made deals with drug makers, research firms, and agricultural giants like DuPont. She now oversees a staff of 44 that spends its time improving the core gene-editing technology. One recent development: a tool called SITE-Seq to help spot when CRISPR makes mistakes.