According to some studies, the presence of elevated levels of pro-inflammatory mediators in the gingival tissues of diabetic patients, such as IL1-β (interleukin 1 beta), tumor necrosis factor (TNF-α), IL-6 (interleukin 6), matrix metalloproteinases (MMPs), prostaglandins (PGs), nuclear factor-kappa B receptor activator ligand/osteoprotegerin relationship (RANK-L/OPG), and oxidative stress, plays an important role in the initiation and progression of periodontal disease [7,8,9,17,18]. The gene discussed is TNF; the disease is periodontal disorder.