Ian Sample speaks to Guardian science correspondent Hannah Devlin about the latest developments and debates about gene editing to emerge from a summit at the Francis Crick Institute in London. The summit heard from the first person with sickle cell disease to be treated with a technique known as Crispr. He also hears from Prof Claire Booth about ensuring these cutting edge treatments are made available to everyone who needs them. Help support our independent journalism at theguardian.com/sciencepod