Investigation on the association of interleukin-1 genotype polymorphism with chronic periodontitis

Objective: To examine the distribution of IL-1 genotypes among the people with Han nationality of different periodontal health status and to evaluate if there is an association between the genotype of IL-1 and the severity of periodontitis.

Methods: 271 subjects of Han nationality were selected, among them there were 182 cases of chronic periodontitis and 89 subjects of periodontal healthy control. Full periodontal examinations were taken including full-mouth clinical attachment loss measurements, probing depths and bleeding on probing. DNA samples were obtained with buccal swabbing technique and were further analyzed for IL-1 genotype polymorphisms using PCR-RFLP-based method.

Results: The results showed a significant increase in the frequency of IL-1A-889/Nco I allele 2, IL-1B + 3953/Taq I allele 2, IL-1B-511/Ava I allele 2, IL-1A-889 plus IL-1B-511 allele 2 and IL-1B + 3953 plus IL-1B-511 allele 2 in patients with severe chronic periodontitis as compared with periodontally healthy controls.

Conclusions: Findings from this study bring into question the usefulness of the genotypes of allele 2 of IL-1A-889, IL-1B-511 and IL-1B + 3953 as a method for determining the susceptibility of Chinese patients to chronic periodontitis. There is a possible role of IL-1 gene polymorphisms in the susceptibility to chronic periodontitis for some patients.