HLA-DRA and Behcet disease: HLA-DRA had significantly reduced expression in the BD (mean = 12.67, sd = 0.32, p = 2.14e-9) and SCH (mean = 12.67, sd = 0.33, p = 4.62e-10) groups compared to the CTRL group (mean = 12.86, sd = 0.31), but no significant difference was found between the patient groups (p = 0.99; see Supplementary Figure S1), suggesting that the underlying immune-related mechanisms are partly similar in the two disorders.