Association analysis of the IL-1 gene cluster polymorphisms with aggressive and chronic periodontitis in the Algerian population.

Objective: There is strong evidence that genetic as well as environmental factors affect the development of periodontitis. Various studies suggest that genetic polymorphisms of the interleukin-1 (IL-1) genes are associated with an increased risk of developing the pathogenesis. The aim of the present study was to investigate the possible relationship between two polymorphisms of IL-1 gene cluster IL-1B (C+3954T) (rs1143634) and IL-1A (C-889T) (rs1800587) SNPs and the aggressive and chronic periodontitis risk in a case control study in Algerian population.

Methods: 279 subjects were recruited and received a periodontal examination: 128 healthy controls and 151 cases. From cases, 91 patients were having a chronic disease whereas 60 subjects with aggressive form. All these subjects were genotyped for IL-1A (C-889T) and IL-1B (C+3954T) polymorphisms using TaqMan real time PCR technology. Frequencies of IL-1 alleles, genotypes and the haplotypes were also examined.

Results: Significant differences were found in the carriage rate of both minor alleles of the IL-1A (C-889T) and IL-1B (C+3954T) polymorphisms of aggressive periodontitis cases compared with healthy controls (OR [95%CI]=1.61 [1.03-2.49], p=0.03), (OR [95%CI]=1.69 [1.09-2.63], p=0.01), respectively. The result did not reach significance with the chronic form.

Conclusions: The studied polymorphisms of the IL-1 genes appear to be associated with susceptibility to aggressive periodontitis (AgP) in the Algerian population.