I’m in a Portakabin in a Tesco car park, somewhere just outside of Wimbledon in South London, about to have what is perhaps the most important blood test I’ve ever had.
Queuing alongside me is a gaggle of people, young and old, all eager to get their samples taken, too.
Together, we are about to become a small handful of the five million volunteers to take part in one of Britain’s most ambitious medical research projects to date.
Launched at