IL-1 Gene Cluster is Not Linked to Aggressive Periodontitis

Abstract

The interleukin-1 (IL-1) gene family has been associated with susceptibility to periodontal diseases, including aggressive periodontitis (AgP); however, the results are still conflicting. The present study investigated the association between IL-1 genes and AgP using 70 markers spanning the 1.1-Mb region, where the IL-1 gene family maps, and exploring both the linkage disequilibrium (LD) and the haplotype structure in a case-control study including 95 patients and 121 control individuals. No association between AgP and IL1A, IL1B, and IL1RN genes was found in either single-point or haplotype analyses. Also, the LD map of the region 2q13-14 under the Malécot model for multiple markers showed no causal association between AgP and polymorphisms within the region (p = 0.207). In conclusion, our findings failed to support the existence of a causative variant for generalized AgP within the 2q13-14 region in an Italian Caucasian population.

Gene–gene interaction among cytokine polymorphisms influence susceptibility to aggressive periodontitis

“…16,17 In a pilot study, we found a weak association of AgP status with both IL-1B( þ 3953) and IL-1RN polymorphisms. 16 However, in a more recent study, conducted on a wider dataset, we failed to support the existence of a causative variant for AgP within the candidate region where IL-1A, IL-1B and IL1RN genes reside.…”

“…These results are consistent with Fiebig et al 43 and with our previous findings, where the association between AgP and IL-1 cluster was investigated in a similar Caucasian cohort by means of pairwise, haplotypes and LD map analyses. 17 As with any association study that evaluates the contribution of a number of candidate variants to a given phenotype, the generalisability of our results to different study cohorts should be cautiously interpreted. Other limitations of the present study include the crosssectional design and the limited sample size, suggesting that our findings should be regarded as preliminary stemming from a pilot study.…”

“…16 However, in a more recent study, conducted on a wider dataset, we failed to support the existence of a causative variant for AgP within the candidate region where IL-1A, IL-1B and IL1RN genes reside. 17 The purpose of this paper was to apply, on a dataset of candidate gene polymorphisms for AgP, different multivariate analysis tools, with the aim to infer biological structures from genetic markers by means of a two-locus epistatic analysis. We firstly used conventional parametric methods for detecting and characterising interactions among the variables, with the aim to reduce the n-dimensional space of the analyses.…”

IL1 cluster gene polymorphisms in macedonian patients with chronic periodontitis

“…The case-control study included 95 patients and 121 control individuals and explored both the linkage disequilibrium (LD) and the haplotype structure. No association between aggressive periodontitis and IL1A, IL1B, and IL1RN genes was found in either single-point or haplotype analyses, and the study failed to support the existence of a causative variant for generalized aggressive periodontitis within the 2q13-14 region in an Italian Caucasian population (41).…”

Single nucleotide polymorphisms in interleukin-1gene cluster and subgingival colonization with Aggregatibacter actinomycetemcomitans in patients with aggressive periodontitis

“…Although a distinct decrease in TT-genotype carrier of IL-1 receptor SNP rs2234650 was detected in AP patients compared with periodontitis-free controls (NS, 5.8% vs 15.7%, Table 2) no significant association of this SNP with the occurrence of severe periodontitis could be proved in our study. Scapoli et al, who investigated 70 markers in the IL-1 gene region in patients with aggressive periodontitis [43], could also not demonstrate an association of SNPs in IL-1R with the occurrence of periodontitis.…”