Customs agents were alarmed at their discovery last August at Dulles International Airport: an undeclared cooler packed in a suitcase and filled with 10 test tubes of an unknown yellowish substance, brought to the U.S. by a woman claiming to be a Russian scientist.

Authorities scrambled to uncover the truth: The woman was indeed a respected Russian scientist. The test tubes were not dangerous, but contained DNA samples of endangered species, including Siberian crane, that were related to her work as a geneticist with the Institute of Molecular and Cellular Biology in Novosibirsk.