According to qRT-PCR, SREBF2 mRNA as increased in COVID-19 patients in a severity-dependent manner, and the level of sestrin 1 (SESN1) and proprotein convertase subtilisin/kexin type 9 (PCSK9), which are known to regulate the lipid biosynthesis, also showed similar increasing trend as the severity of COVID-19 increases (Supplementary Fig. 2). Here, PCSK9 is linked to COVID-19.