MT-ND2 and COVID-19: In this study, top abundant DEGs such as genes encoding for ribosomal protein (RPL4), controlling the production of the mitochondrial reactive oxygen species (MT-ND2) (43), modulating cell proliferation and differentiation (SCD5) (44), mitochondrial deficiencies and associated disorders (MT-CYB) (45), epithelial marker ezrin (EZR) associated with cell surface structure adhesion, migration and organization of the SARS-CoV-2 (46) were found to be co-expressed in the nasopharyngeal epithelial cells of COVID-19 patients and recovered humans (Figure 2C).