OBJECTIVETo 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.

METHODS271 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.

RESULTSThe 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.

CONCLUSIONFindings 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.