Methods: The study population consisted of Japanese adults with RA (RA: n=64), periodontitis only (P: n=100), and healthy individuals (H: n=100). Clinical periodontal condition was defined by measurements of probing depth, clinical attachment level, and bleeding on probing. Genomic DNA was isolated from peripheral blood, and analyzed for genotyping of 29 gene polymorphisms by Invader DNA chips or polymerase chain reactions-Invader assay.
Results: The RA groups exhibited more mild levels of periodontal tissue destruction than the P group. A significant difference was observed in the matrix metalloproteinase-3 (MMP-3) genotype and the vitamine D receptor (VDR) allele frequencies between the RA and H groups (p = 0.048 and p = 0.037), and also in the interleukin-1B (IL-1B) –31 genotype frequency between the RA and P groups (p= 0.043).
Conclusion: These results suggest that the distributions of MMP-3, VDR, and IL-1B –31 genotypes were unique to patients with RA and periodontitis in a Japanese population.
This work was supported by Grant-in-Aid for Scientific Research (19592383) from the Japan Society for the Promotion of Science, Japan.