By combining results of common blood tests, the researchers were able to come up with a way to predict risk of diabetes and other chronic diseases. Martynasfoto/Getty Images/iStockphoto hide caption

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Martynasfoto/Getty Images/iStockphoto

Whether or not you'll someday get cancer or any disease can feel like a roll of hundreds of dice. Calculating the odds --€” and knowing what they mean --€” is tricky. Katie Harbath/Flickr hide caption

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Katie Harbath/Flickr

Angelina Jolie took a genetic test to find out her risk of breast cancer, and had a preventive double mastectomy. Alastair Grant/PA Photos /Landov hide caption

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Alastair Grant/PA Photos /Landov