Smoking and Polymorphisms of the Interleukin‐1 Gene Cluster (IL‐1β, IL‐1α, and IL‐1RN) in Patients with Periodontal Disease

Background: Polymorphisms within the interleukin-1 cluster are known to be associated with adult periodontal disease. However, interactions of genetic with other risk factors, especially smoking, remain questionable. The aim of this cross-sectional study was to evaluate the genetic influence on periodontal variables in relation to environmental factors. Methods: One-hundred fifty-four (154) Caucasian subjects were clinically and radiographically assessed for their periodontal status, their smoking history recorded, and their allelic pattern of IL-1α, IL-1β, and IL-1RN polymorphisms determined by genotyping. Results: In assessing periodontitis with mean probing depth, mean attachment loss, or mean bone loss, no differences were found in allele frequencies or combined allotypes between subjects with mild or moderate versus those with severe signs of periodontitis. However, the extent of attachment loss defined as percentage of sites >4 mm was signifi- cantly associated with the composite genotype of IL-1α/1...