Second, a bidirectional two-sample MR analysis was conducted using pooled statistics ofparticipating MS from GWAS to investigate the potential causal relationship between MS patients treated with IFNβ and three types of COVID-19 phenotypes (SARS-CoV-2 infection, hospitalized COVID-19, and severe COVID-19). The gene discussed is IFNB1; the disease is myeloid sarcoma.