IL1A and periodontitis: An increased risk of developing periodontitis is associated with genetic polymorphisms of IL1A, IL1B, IL6, and TNFA genes [14,38] and MMP-9 (−1562C/T) [73], ANRIL rs1333048, rs1333042, rs2891168, and rs496892 polymorphisms might have impact on susceptibility to periodontitis, especially in Caucasian individuals [74].