TYK2 and COVID-19: The COVID-19 Host Genetics Initiative (HG1) report concurred with the association of variants in ABO, SLC6A20, TYK2, DPP9, IFNAR2, and additionally reported a variant in Protein Phosphatase 1 Regulatory Subunit 15A (PPP1R15A) in influencing COVID-19 severity [27].