A scientist works in a laboratory at the Oxitec Ltd., company headquarters in Abingdon, U.K., on Wednesday, April 18, 2012. U.K. biotechnology start-up Oxitec Ltd. wants to start U.S. tests of a new weapon in the war on dengue fever: genetically modifying mosquitoes that carry the disease so that their progeny self-destruct. Photographer: Simon Dawson/Bloomberg via Getty Images
