For example, it has been reported that tissue affected by periodontitis and normal periodontal tissue show differences in the methylation status of promoters for inflammation-related genes such as those encoding interleukin (IL)-8, tumor necrosis factor-alpha (TNFα) and toll-like receptor-2 (TLR2) [10,11,12,13]. The gene discussed is TLR2; the disease is periodontitis.