ACE2 (adjusted p value [q] = 0.053, Fig. 3a and Supplementary Table 7), as well as TMPRSS2 (q = 8.1 × 10−10) and FURIN (q = 4.2 × 10−6, Supplementary Fig. 3b), have elevated expression in squamous cells from male patients with both moderate and critical COVID-19 compared to females. Here, ACE2 is linked to COVID-19.