Plasma MT-CYTB levels were elevated in those subjects with COVID-19 who required an ICU admission [7.52 (7.14–7.72), n = 55] compared with those who were not admitted to the ICU [7.13 (7.00–7.31), P < 0.0001, n = 42, Figure 3A]. This evidence concerns the gene MT-CYB and COVID-19.