DNA methylation profile of genes related to immune response in generalized periodontitis

BACKGROUND AND OBJECTIVE: Epigenetic events, as the DNA methylation, may be related to development of inflammatory diseases. Due to the important role of host's response in the pathogenesis of periodontitis, the purpose of the present study was to investigate the methylation profile of genes related to immune response in gingival tissues from patients with generalized periodontitis (GP) compared to healthy individuals. METHODS: Gingival tissues were collected from 20 individuals with GP and 20 healthy individuals. Genomic DNA was extracted and submitted to enzymatic digestions. An initial screening using a panel of genes involved with the response immune was performed in pools containing six samples of each group. Genes that presented different levels of methylation between the groups were selected for individual assays for validation. RESULTS: The array results showed an unmethylated profile in the majority of genes evaluated in both groups. MALT1, LTB, and STAT5 genes presented a profile of partial methylation in the control compared with GP group. Validation individual assays using a larger number of samples (n = 20, each group) confirmed the hypomethylation of STAT5 in the GP group compared with control group (P < .001). CONCLUSION: Generalized periodontitis is associated with hypomethylation of the STAT5 gene. Further studies are necessary to evaluate the functional impact these findings.