title: Association between polymorphisms in interleukin-17A and -17F genes and chronic periodontal disease.
abstract: OBJECTIVE
  Interleukin-17 (IL-17) is a cytokine that induces neutrophil recruitment and the release of inflammatory mediators in several inflammatory conditions; nevertheless, the involvement of IL-17 gene polymorphisms in chronic periodontitis (CP) has not been addressed yet. Our aim was to evaluate the association between periodontal status and the polymorphisms IL-17A G197A and IL-17F C7488T in subjects with CP along with their impact on levels of inflammatory mediators.
  
  
  METHODS
  Genomic DNA was obtained from 30 CP patients and 30 healthy controls (HCs). IL-17A G197A and IL-17F C7488T polymorphisms were determined using PCR-RFLP. Serum and periodontal tissues were collected and processed for ELISA, myeloperoxidase (MPO), and/or microscopic analysis.
  
  
  RESULTS
  The frequencies of genotypes in the CP group were significantly different from those of HC. Odds ratio indicated that increased risks for CP were associated with the -197A allele, not with the -7488T allele. In addition, the -197A allele was correlated with worse clinical parameters, higher MPO activity, and increased expression of inflammatory mediators (IL-17A and IL-8) than the other genotypes.
  
  
  CONCLUSIONS
  These results indicate that the IL-17A -197A allele is associated with increased risk for CP, likely because this genotype relates to the enhanced inflammation in periodontal tissues.
authors.affiliation: Departmento de Clínica, Patologia e Cirurgia Odontológicas, Faculdade de Odontologia, Universidade Federal de Minas Gerais, 31.270-901 Belo Horizonte, MG, Brazil.
authors.forename: Jôice Dias
authors.initials: JD
authors.lastname: Corrêa
authors.forename: Mila Fernandes Moreira
authors.initials: MF
authors.lastname: Madeira
authors.forename: Renata Gonçalves
authors.initials: RG
authors.lastname: Resende
authors.forename: Jeane de Fátima
authors.initials: Jde F
authors.lastname: Correia-Silva
authors.forename: Ricardo Santiago
authors.initials: RS
authors.lastname: Gomez
authors.forename: Danielle da Glória
authors.initials: Dda G
authors.lastname: de Souza
authors.forename: Mauro Martins
authors.initials: MM
authors.lastname: Teixeira
authors.forename: Celso Martins
authors.initials: CM
authors.lastname: Queiroz-Junior
authors.forename: Tarcília Aparecida
authors.initials: TA
authors.lastname: da Silva
mesh_terms: D000328:Adult; D055113:Chronic Periodontitis / Q000235:genetics* / Q000276:immunology; D005260:Female; D006801:Humans; D020381:Interleukin-17 / Q000032:analysis / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D010519:Periodontium / Q000737:chemistry; D009195:Peroxidase / Q000378:metabolism; D020641:Polymorphism, Single Nucleotide
chemical_list: C508717:IL17A protein, human; C440021:IL17F protein, human; D020381:Interleukin-17; D009195:Peroxidase