PTTG1 and COVID-19: The final 20 genes with greatest performance in classifying COVID-19 patients from healthy individuals were dominated by genes from modules of the Cell Cycle (CCNB1, CCNB2, CDC20, CEP55, GINS2, MCM10, MKI67, PTTG1) and OxPhos (COX6C, COX7B, COX7C, NDUFAF5, NDUFAF7, NDUFB3, TMEM126B, UQCRB) but also included genes in the Glycolysis (SLC2A3), and Granulocyte (CD177, CLC, OSM) modules (Figure 2D and Figure S1B, Table S3).