A forthcoming study from genetic testing giant 23andMe shows that a person’s genetic code could be connected to how likely they are to catch Covid-19 — and how severely they could experience the disease if they catch it. It’s an important confirmation of earlier work on the subject. People whose blood group is O seemed to test positive for Covid-19 less often than expected when compared to people with any other blood group, according to 23andMe’s data; people who tested positive and had a specific variant of another gene also seemed to be more likely to have serious respiratory symptoms. The study, which was released on a preprint server and which has not yet been peer-reviewed … Experts who aren’t affiliated with 23andMe praised the study design and the work.