TNF and periodontitis: Out of the most studied genes in aggressive periodontitis [IL1-A and IL1-B (2q14), IL-4 (5q31.1), IL-10 (1q31-q32), FcγRIIa, FcγRIIb, and FcγRIIIb (1q23), and TNFA (6p21.3)], IL-4 and TNFA map in the intervals with suggestive association results.