Microbiological parameters associated with IL-1 gene polymorphisms in periodontitis patients

Area of Science:

• Periodontology
• Genetics
• Microbiology

Background:

• Interleukin-1 (IL-1) gene polymorphisms are associated with adult periodontitis severity.
• Understanding the microbiological differences between IL-1 genotype positive and negative individuals is crucial.

Purpose of the Study:

• To compare microbiological parameters in adult periodontitis patients based on IL-1 gene (IL-1A and IL-1B) genotype status.
• To investigate the relationship between IL-1 genotype and the levels of specific subgingival bacteria.

Main Methods:

• 108 systemically healthy adults with periodontitis were studied.
• Clinical parameters and subgingival plaque samples were collected from 2736 sites.
• Checkerboard DNA-DNA hybridization identified 40 subgingival taxa; PCR determined IL-1A and IL-1B genotypes.

Main Results:

• IL-1 genotype positive subjects had significantly higher mean counts of specific subgingival species compared to genotype negative subjects.
• Elevated levels of "red" and "orange" complex bacteria (e.g., Bacteroides forsythus, Porphyromonas gingivalis, Treponema denticola) were observed in genotype positive individuals.
• Higher bacterial counts in genotype positive subjects were noted particularly in periodontal pockets >6 mm.

Conclusions:

• Adults with IL-1 gene polymorphisms are more likely to harbor higher levels of "red" and "orange" complex bacterial species.
• These findings suggest a link between IL-1 genotype and the presence of key periodontal pathogens associated with inflammation.