Researcher Hilary Gunn tests wheat DNA with a PCR machine in a lab at Oregon State University (OSU) in Corvallis, Oregon, U.S., Friday, June 7, 2013. Several plant scientists questioned conclusions Monsanto Co. drew from its investigation of an escaped gene-altered wheat variety and said there is still a risk that rogue grain is in the seed supply. Photographer: Natalie Behring/Bloomberg via Getty Images
