The Heroes of CRISPR

Three years ago, scientists reported that CRISPR technology can enable precise and efficient genome editing in living eukaryotic cells. Since then, the method has taken the scientific community by storm, with thousands of labs using it for applications from biomedicine to agriculture. Yet, the preceding 20-year journey-the discovery of a strange microbial repeat sequence; its recognition as an adaptive immune system; its biological characterization; and its repurposing for genome engineering-remains little known. This Perspective aims to fill in this backstory-the history of ideas and the stories of pioneers-and draw lessons about the remarkable ecosystem underlying scientific discovery.