In gingival fibroblasts, DNMTs are also regulated by inflammatory mediators that play a central role in periodontitis pathogenesis: IL-1β upregulates DNMT1 and downregulates DNMT3a expression, whereas exposure to PGE2 leads to downregulation of both DNMT1 and DNMT3a [116]. The gene discussed is DNMT1; the disease is periodontitis.