On November 26, the World Health Organization designated the strain of coronavirus surging in South Africa a "variant of concern" and christened it Omicron. The next day, University of British Columbia professor Sriram Subramaniam downloaded a genome sequence posted online and ordered samples of Omicron DNA to be shipped to his lab. Subramaniam's group uses electron microscopes to reveal the 3D structure of proteins, to better understand how they work. It had already mapped the spike proteins that coronaviruses use to bind and enter human cells for some earlier strains. Describing Omicron's spike protein felt urgent because its DNA differed in ways that might explain the variant's rapid spread.