The first person has been treated with a highly anticipated new gene therapy that aims to turn back the clock on ageing cells. The trial is aimed at retinal cells, with the hope that encouraging them to behave as if they were young again could improve sight in the affected patients. If it proves to be safe, it could open the door to a whole raft of therapies based on the emerging field of cellular rejuvenation. To understand more about this cutting edge research, Madeleine Finlay hears from science editor Ian Sample and from Paul Knoepfler, professor of cell biology and human anatomy at the university of California, Davis.. Help support our independent journalism at <a href="https://www.theguardian.com/sciencepod">theguardian.com/sciencepod</a>
