Several studies showed an association of OLP with the presence of lymphocyte infiltrate of CD4 + and CD8 + lymphocytes at the level of the connective epithelial interface and functional polymorphisms in the regulatory regions of the genes coding for the proinflammatory cytokines tumor necrosis factor-alpha (TNF-α), interleukin-12 (IL-12), IL-18, and chemokines CXCL9 and CXCL10.5, 6, 7, 8. The gene discussed is TNF; the disease is oral lichen planus.