For severe cases of COVID-19, neutrophils (>81%), lymphocyte (≤25.4%), absolute lymphocyte count (≤1.38×103/μL), absolute eosinophil count (≤0.03×103/μL), total bilirubin (≥0.51 mg/dL), A/G ratio (≤1.49), albumin (≤4.2 g/dL), ferritin (≥445.4 mg/dL), LDH (≥479 U/L), IL-6 (≥28.6 pg/mL), CRP/ALB ratio (≥1.78), D-dimer (≥237 ng/mL), and fibrinogen (≥425 mg/dL) are also crucial biomarkers. The gene discussed is IL6; the disease is COVID-19.