In 2014, India’s Dutee Chand was a rising female track and field star, crushing national records. But then, that summer, something unexpected happened: she failed a gender test. And was banned from the sport. Before she knew it, Dutee was thrown into the middle of a controversy that started long before her, and continues on today: how to separate males and females in sport. First aired in 2018, Dutee and the story of female athletes in sport are back in the spotlight this week, at the Tokyo Olympics. Join us for an update on Dutee’s second Olympic games, and the continued role testosterone has in shaping who is on the track, and who is off.  This story was originally released as part of Gonads, a six-part series on the parts of us that make more of us. It is a companion piece to Gonads, episode 5: Dana. This update was reported by Molly Webster, with reporting and producing by Sarah Qari. "Dutee" was reported by Molly Webster, with co-reporting and translation by Sarah Qari. It was produced by Pat Walters, with production help from Jad Abumrad and Rachael Cusick. The Gonads theme was written, performed, and produced by Majel Connery and Alex Overington. Special thanks to Geertje Mak, Maayan Sudai, Andrea Dunaif, Bhrikuti Rai, Joe Osmundson, and Payoshni Mitra. Plus, former Olympic runner Madeleine Pape, who is currently studying regulations around female, transgender, and intersex individuals in sport. Radiolab is supported in part by Science Sandbox, a Simons Foundation initiative dedicated to engaging everyone with the process of science. And the Alfred P. Sloan Foundation, enhancing public understanding of science and technology in the modern world. More information about Sloan at www.sloan.org. Support Radiolab today at Radiolab.org/donate.