The H1N1 swine flu virus kills some people, while others don't get very sick at all. A genetic variation offers one clue. Centre For Infections/Health Pro/Science Photo Library/Getty Images hide caption

itoggle caption Centre For Infections/Health Pro/Science Photo Library/Getty Images

MaryAnn Anselmo has started to sing again after recovering from brain surgery and having successful treatment with a drug that targeted a mutation in her tumor cells. Dave Gershgorn/WNYC hide caption

itoggle caption Dave Gershgorn/WNYC

A simulation from the Neitz lab of what colorblindness looks like, with normal color vision on the left and red-green colorblindness on the right. Courtesy of Neitz Laboratory hide caption

itoggle caption Courtesy of Neitz Laboratory

The Josephson family in 2001, after Dixie (third from left) was told she had cancer. Courtesy of the Josephsons hide caption

itoggle caption Courtesy of the Josephsons

Central Illinois corn farmer Jerry McCulley refills his sprayer with the weedkiller glyphosate on a farm near Auburn, Ill. A new assessment of the chemical finds that the (uncertain) risks mainly affect the people who work with it or who come in direct contact with areas where it's applied. Seth Perlman/AP hide caption

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Both James Eversull (left) and Pat Patchell were treated with experimental chemotherapy and radiation for leukemia as children in the 1960s. Together, they're now some of the country's oldest leukemia survivors.. Courtesy of James Eversull; Courtesy of Pat Patchell hide caption

itoggle caption Courtesy of James Eversull; Courtesy of Pat Patchell

Celebrity chef Giada De Laurentiis during a guest appearance on ABC's The Chew last fall. She can cook rich foods and keep her trim figure, but new research suggests that's a difficult feat for amateur cooks watching along at home. Lou Rocco/ABC/Getty Images hide caption

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