A vast store of DNA is being used to study why the severity of symptoms for coronavirus varies so much.
UK Biobank – which contains samples from 500,000 volunteers, as well as detailed information about their health – is now adding Covid-19 data.
It is hoped genetic differences could explain why some people with no underlying health conditions can develop severe illness.
More than 15,000 scientists from around the world have access to UK Biobank.
Prof Rory Collins, principal investigator of the project, said it would be “a goldmine for researchers”.
“We could go very quickly into getting some very, very important discoveries,” he said.
How do Covid-19 symptoms differ?
Some people with coronavirus have no symptoms – and scientists are trying to establish what proportion this is.