Kari Stefansson is in a hurry. The president and CEO of deCODE genetics must get across town to see a former colleague at Beth Israel Deaconess hospital before dashing to the airport-and he still needs to squeeze in a promised interview with a journalist. In the cab, he alternates between discussing travel plans in Icelandic with a coworker and expounding on the intersection of disease and human evolution in English with TR associate editor Erika Jonietz.

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