Then we analyzed the gene expression levels of these hub genes, and found that, compared with controls, the expression level of NOTCH1 (t75 = 2.159, P = 0.034), NGF (t75 = 3.183, P = 0.002), and POMC (t75 = 3.791, P = 3e-04) presented significant up-regulation in BD (Supplementary Figure 4). Here, NOTCH1 is linked to Behcet disease.