November 30, 2021 11:36 PMNEW YORK (NYTIMES) - The Omicron variant of the coronavirus has alarmed many scientists because of the sheer number of genetic mutations it carries - about 50 in all, including at least 26 that are unique to it. But more does not necessarily mean worse: Mutations sometimes work together to make a virus more fearsome, but they may also cancel one another out.