Subgingival microbiota and genetic factors (A-2570G, A896G y C1196T TLR4 polymorphisms) as periodontal disease determinants

Raúl Castro-Casarrubias¹Natividad Castro-Alarcón¹Salvador Reyes-Fernández²Elena Salazar-Hernández¹Mirna Vázquez-Villamar³Norma Samanta Romero-Castro^2*

• ¹Autonomous University of Guerrero, Chilpancingo, Guerrero, Mexico
• ²Universidad Autónoma de Guerrero, Acapulco, Guerrero, Mexico
• ³Universidad Autónoma de Guerrero, Iguala, Guerrero, Mexico

The subgingival microbiota plays an important role in the maintaining of oral health. Subgingival dysbiosis leads to the aggregation of highly pathogenic bacteria, and host genetics modulate the innate immune response. The interaction between these two factors plays an important role in the aggravation of periodontitis. Therefore, evaluating the association between the TLR 4 polymorphisms and subgingival microbiota in patients with periodontitis is necessary. Methods: Study 58 cases with periodontitis and 53 controls without periodontitis. The A896G, A-2570G, and C1196T polymorphisms of the TLR4 gene were determined by PCR-RFLP. The DNA-DNA checkerboard hybridization technique carried out the identification and quantification of 18 bacterial species of subgingival plaque. Results: Cutibacterium acnes occurred in greater number and frequency than other bacterial species (χ ̅ 1.32 E+05) in individuals with periodontitis.Patients with C. acnes have a higher risk (OR= 3.82 [95% CI: 1.37-10.3]) of developing periodontitis (p < 0.05), as well as those with orange and red complex bacteria (T. denticola, T. forsythia, P. gingivalis, P. nigrescens, P. intermedia, F. periodonticum, F. nucleatum, E. nodatum, and C. rectus). The A/G genotype of SNP -2570 of the TLR4 gene were identified as a risk factor for the development of periodontitis (OR= 2.28 [95% CI:1.04-5.00]). While an antagonistic biological effect about the presence of bacteria such as Capnocytophaga gingivalis ) and Campylobacter rectus (OR=0.39 [95% CI: 0.18-0.87]) (p< 0.05). The A/G genotype of SNP -2570 is correlated with the greater clinical attachment loss and periodontal pocket depth. Conclusions: The agonistic or antagonistic biological effect of each bacterial species will depend on the genotype present in each individual, and the destruction processes of dental support tissues.