IL1A and periodontitis: Considering results for GCP and GAgP patients together, the presence of polymorphism in IL-1A and/or IL-1B gene was associated with a higher likelihood of periodontitis, (OR = 8.11; 95%CI [1.85–35.48]), but this likelihood was reduced when IL-1RN polymorphism was also present, (OR = 5.91; 95%CI [1.08–32.27]).