Behcet’s Disease (BD) is a multisystem chronic inflammatory disease. The pathology is believed to involve both genetic susceptibility and environmental factors. Hypomethylation leading to activation of interspersed repetitive sequences (IRSs) such as LINE-1 and Alu contributes to the pathologies of autoimmune diseases and cancer. Herein, the epigenetic changes of IRSs in BD were evaluated using combined bisulfite restriction analysis-interspersed repetitive sequences (COBRA-IRS). DNA from neutrophils and peripheral blood mononuclear cells (PBMCs) of BD patients with ocular involvement that were in active or inactive states and healthy controls were used to analyze LINE-1 and Alu methylation levels. For Alu sequences, significant differences were observed in the frequency ofCuCualleles between PBMCs of patients and controls (p=0.03), and between inactive patients and controls (p=0.03). For neutrophils, the frequency ofCuCuwas significantly higher between patients and controls (p=0.006) and between inactive patients and controls (p=0.002). The partial methylation (CuCm+CmCu) frequencies of Alu between inactive patients and control samples also differed (p=0.02). No statistically significant differences for LINE-1 were detected. Thus, changes in the methylation level of IRS elements might contribute to the pathogenesis of BD. The role of Alu transcripts in BD should be investigated further.
Methylation status of interleukin-6 gene promoter in patients with Behçet's disease
