IL1RN and chronic periodontitis: Relevant associations have been found, for instance, in genetic polymorphisms in genes such as IL1B, IL1RN, FcγRIIIb, VDR, and TLR4 in connection to susceptibility to aggressive periodontitis; and in IL1B, IL1RN, IL6, IL10, VDR, CD14, TLR4, and MMP-1 related to chronic periodontitis (Laine et al., 2012).