On the contrary, mRNA expression of MUC16 was significantly increased in the mild patient groups compared with controls and the critically ill COVID-19 patients, whereas expression of MUC20 mRNA was significantly decreased in the critically ill COVID-19 group compared with controls and the mild patient groups (Figure 2B, Figure 3, D and E, and Supplemental Figure 1A). This evidence concerns the gene MUC20 and COVID-19.