Finally, the construction of the nomogram, as depicted in Fig. 7C, resulted in an AUC of 0.816 (95% CI: 0.723–0.909), indicating significant clinical diagnostic value, as demonstrated in Fig. 7D. Similarly, BD showed the up-regulation of genes E2F1 and HDAC5, as well as the down-regulation of genes GATA3 and MSH2, as shown in Supplementary Fig. S2A. Here, HDAC5 is linked to Behcet disease.