Considering that some IL-8 polymorphisms were previously reported to be associated with higher IL-8 production and that a significantly higher level of this protein was found in the gingival crevicular fluid from patients with periodontitis [56], we hypothesize that the genetic differences between individuals in relation to IL-8 production may somehow predispose them to periodontal disease. The gene discussed is CXCL8; the disease is periodontitis.