In particular, MPO-DNA complexes were correlated with Sequential Organ Failure Assessment (SOFA) score (Spearman r = 0.398, p = 0.036) and were significantly higher in COVID-19 patients admitted to intensive care units, whereas partial pressure of alveolar oxygen /fraction of inspired oxygen (PaO2/FiO2) correlated inversely (Spearman r = −0.403, p = 0.034) in a study of 28 hospitalized patients (age mean = 55.1 years, 60% male, 64.3% with diabetes, 46.5% with hypertension, 39.3% with chronic lung disease, 53.6% with ARDS) [74,81]. This evidence concerns the gene MPO and COVID-19.