Specifically, the COVID-19 susceptibility rs10774671-A allele, as well as linked alleles of many other variants in this region, was associated with decreased basal OAS enzymatic activity in unstimulated PBMCs from healthy individuals11, impaired clearance of West Nile virus infection27, chronic hepatitis C virus infection28, impaired SARS-CoV clearance29, and increased susceptibility to several autoimmune conditions (multiple sclerosis30,31, Sjögren’s syndrome32 and systemic lupus erythematosus33,34). Here, SMOC1 is linked to COVID-19.