The scientific legacy of Dolly the sheep

Twenty years ago, British scientists introduced the world to Dolly the sheep, the first mammal to be cloned using nuclear transfer. She only lived for seven years, but the scientific advances that came from her creation continue. Al Jazeera's Barnaby Phillips reports from London. Subscribe to our channel: http://aje.io/AJSubscribe Follow us on Twitter:   / ajenglish   Find us on Facebook:   / aljazeera   Check our website: http://www.aljazeera.com/