In COVID-19-positive group, CT score median value was significantly higher in patients with KL-6 > 400 U/mL than in patients KL-6 ≤ 400 U/mL (12.00, IQR 5.00–18.00 versus 4.50, IQR:3.75–7.25; p-value 0.027) (Fig. 5a). The gene discussed is MUC1; the disease is COVID-19.