GDNF and Behcet disease: Among them, CXCL1 (IVW: OR = 1.066, 95% CI: 1.003–1.133, p= 0.041; Figure S39), FGF‐5 (IVW: OR = 1.048, 95% CI: 1.005–1.093, p= 0.027; Figure S41), and hGDNF (IVW: OR = 1.094, 95% CI: 1.023–1.171, p= 0.009; Figure S42) were risk factors for BD, while CXCL5 (IVW: OR = 0.944, 95% CI: 0.901–0.99, p= 0.018; Figure S40), HGF (IVW: OR = 0.879, 95% CI: 0.792–0.976, p= 0.016; Figure S43), and IL‐20 (IVW: OR = 0.900, 95% CI: 0.813–0.995, p= 0.040; Figure S44) were protective against BD.