The meta-analysis of seven studies [15, 16, 19–21, 23, 25] further suggested a higher level of serum galectin-3 in patients with AECOPD compared to stable COPD (SMD ═ 0.33, 95% CI 0.20–0.46; P < 0.001; I2 ═ 0%; Figure 5A). The gene discussed is LGALS3; the disease is chronic obstructive pulmonary disease.