LONDON – Leading genome sequencing groups are launching the first meta-analysis in the hunt for genetic factors that explain why some people have worse COVID-19 symptoms than others, after agreeing to share patient sequence data from around the world. The COVID-19 Host Genetics Initiative (CHGI), set up by scientists at the Institute for Molecular Medicine Finland (FIMM), now includes 151 registered studies that are searching for genetic variation associated with severity and outcomes.