First, 19 genes significantly associated with COVID-19/HCC were identified through univariate Cox analysis, including ADM, ADRB2, ALPL, ANGPT2, CD4, CXCL2, CXCL5, FGA, FGB, G6PD, IKBKE, IL6ST, MAPT, MMP12, PLG, RBP4, SERPINE1, TNNI3 and TTR (P <0.05, Figure 2C and Table 1). The gene discussed is RBP4; the disease is COVID-19.