IL-18 gene promoter polymorphisms are only moderately associated with periodontal disease in Italian population

Objective. The aim of this study was to determine the impact of the polymorphisms at position -607 (C/A) and -137 (G/C) in the promoter of the IL-18 gene and their haplotypes, on the individual susceptibility of developing Aggressive (AgP) and/or Chronic (CP) periodontitis. Materials and methods. A total of 213 unrelated Italian subjects with periodontitis (AgP=109 and CP=104) and 100 periodontal-health subjects were studied. IL-18 gene promoter polymorphisms were analyzed by TaqMan® SNP Genotyping Assays. Genotype and allele frequencies were analyzed using the chi-square test and multiple logistic regression analysis. Results. χ2 of comparisons between diseased patients and healthy controls indicated a significant differentiation between the control and AP and CP groups (χ2=26.359, P