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Katherine Basil

(<a href='http://www.shutterstock.com/gallery-487144p1.html'>bikeriderlondon</a>, <a href='http://www.shutterstock.com/gallery-1096643p1.html'>Tarchyshnik Andrei</a> via <a href='http://www.shutterstock.com/'>Shutterstock</a>/Salon)

Scientists are untangling our bodies’ genetic “double-edged swords”

Katherine Basil