Česká Stomatologie a Praktické Zubní Lékařství (Dec 2011)

Variability in Toll-like Receptor Genes and Their Relation to Occurrence of Periodontal Pathogens in Chronic Periodontitis

  • L. Izakovičová Hollá,
  • B. Hrdličková,
  • J. Vokurka,
  • P. Augustín,
  • A. Fassmann,
  • J. Vaněk

DOI
https://doi.org/10.51479/cspzl.2011.018
Journal volume & issue
Vol. 111, no. 5
pp. 107 – 116

Abstract

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Introduction: Toll-like receptors (TLRs) belong to the pattern recognition receptor family of signal molecules that recognize heterogeneous antigens. The aim of this study was to analyze polymorphisms in the TLR genes and their association with the presence of selected periodontal pathogens and clinical manifestation of chronic periodontitis (CP). Methods: Two polymorphisms in TLR-2, two SNPs in TLR-4 and three variants in TLR-9 genes were studied in 216 patients with CP and 184 unrelated controls. All polymorphisms were detected using the PCR-RFLP methods. The subgingival presence of 7 selected periodontal pathogens was investigated by the VariOr®Dento test. Results: No significant differences were found in frequencies of alleles or genotypes of all polymorphisms in the TLR-2, TLR-4 and TLR-9 genes between patients with CP and controls. However, in a complex analysis, significant differences in frequencies of TLR-9 haplotypes were determined between both groups. Haplotype TLR-9 "TTA" was significantly more frequent (9.8% vs. 2.8%, p < 0.00005) and haplotype "TTG" less frequent (33.7% vs. 41.3%, p = 0.03) in patients with CP in comparison with controls.We did not find significant differences in frequencies of TLR-2 and TLR-4 haplotypes between both groups. Comparison of the occurrence of the selected periodontal pathogens confirmed significant differences in frequencies of P. gingivalis, T. forsythensis, P. micros, P. intermedia. (p < 0.01) and marginal differences in the occurrence of T. denticola and F. nucleatum (p < 0.05) between the group of patients and controls. In contrast, no significant difference between both groups was found for A. actinomycetemcomitans. No significant associations between CP, periodontal pathogens and TLR-2 or TLR-9 polymorphisms was observed in any group; however, we found marginal correlation of both TLR-4 variants with the occurrence of P. gingivalis (p = 0.05). Conclusions: In conclusion, these findings suggest that TLR-9 haplotypes may be associated with susceptibility to chronic periodontitis and indicate a possible interaction between the occurrence of some bacteria in the subgingival plaque and polymorphisms in the TLR-4 gene; this finding is in agreement with multifactorial etiology of this disease.

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