Background: Coronavirus disease 2019 (COVID-19) has caused a large global pandemic. Patients with COVID-19 exhibited considerable variation in disease behavior. Pervious genome-wide association studies (GWAS) have identified potential genetic factors involved in the risk and prognosis of COVID-19, but the underlying biological interpretation remains largely unclear. Methods: We applied the summary data-based Mendelian randomization (SMR) method to identify genes that were pleiotropically/potentially causally associated with the risk and various outcomes of COVID-19, including severe respiratory confirmed COVID-19 and hospitalized COVID-19. The GWAS summarized data for COVID-19 were provided by the COVID-19 Host Genetics Initiative and the Severe Covid-19 GWAS Group. Analyses were done for blood and lung, respectively. Results: In blood, we identified 2 probes, ILMN_1765146 and ILMN_1791057 tagging IFNAR2, that showed pleiotropic association with hospitalized COVID-19 (beta [SE]=0.42 [0.09], P=4.75E06 and beta [SE]=-0.48 [0.11], P=6.76E06, respectively). Although no other probes were significant after correction for multiple testing in both blood and lung, multiple genes as tagged by the top 5 probes were involved in inflammation or antiviral immunity, and several other tagged genes, such as PON2 and HPS5, were involved in blood coagulation. Conclusion: We identified IFNAR2 and other potential genes that could be involved in of the susceptibility or prognosis of COVID-19. These findings provide important leads to a better understanding of the mechanisms of cytokine storm and venous thromboembolism in COVID-19 and potential therapeutic target for effective treatment of COVID-19.
Pleotropic association between risk and prognosis of COVID-19 and gene expression in blood and lung: A Mendelian randomization analysis