title: A functional interleukin-1 beta gene polymorphism is associated with chronic periodontitis in a sample of Brazilian individuals.
abstract: BACKGROUND
  Interleukin-1 beta (IL-1 beta) is a potent inflammatory mediator and an important polymorphism in the locus +3954 (C/T) of the human IL1 B gene has been shown to affect the levels of this cytokine. This functional polymorphism has been associated with the establishment of inflammatory diseases, including periodontal disease, in European, Asian and North American populations.
  
  
  OBJECTIVE
  The aim of this study was to investigate the association between the IL1 B (+3954) gene polymorphism and the occurrence of different clinical forms of periodontitis in a sample of Brazilian individuals.
  
  
  METHODS
  This study employed a cross-sectional design involving individuals from the State of Minas Gerais in the south-eastern region of Brazil. Genomic DNA was obtained from oral swabs of 129 individuals and amplified using the polymerase chain reaction (PCR) with specific primers flanking the locus +3954 of IL1 B. PCR products were submitted to restriction endonuclease digestion and analyzed by polyacrylamide gel electrophoresis, to distinguish alleles T and C of the IL1 B gene, allowing for the determination of the genotypes and detection of the polymorphism.
  
  
  CONCLUSIONS
  The chronic periodontitis group displayed a higher percentage of the T allele (28%) when compared to the aggressive periodontitis group (10.7%, chi(2)=5.24, p=0.02, OR=0.31, CI=0.11--0.88) and to control group (8.7%, chi(2)=7.11, p=0.007, OR=0.24, CI=0.08--0.73). Our data suggested that the polymorphism in the locus +3954 of IL1 B gene could be a risk factor for chronic periodontitis in a sample of Brazilian individuals.
authors.affiliation: Laboratory of Cell-Cell Interactions, Department of Morphology, School of Dentistry, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil.
authors.forename: Paula R
authors.initials: PR
authors.lastname: Moreira
authors.forename: Alessandra R
authors.initials: AR
authors.lastname: de Sá
authors.forename: Guilherme M
authors.initials: GM
authors.lastname: Xavier
authors.forename: José E
authors.initials: JE
authors.lastname: Costa
authors.forename: Ricardo S
authors.initials: RS
authors.lastname: Gomez
authors.forename: Kenneth J
authors.initials: KJ
authors.lastname: Gollob
authors.forename: Walderez O
authors.initials: WO
authors.lastname: Dutra
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001938:Brazil; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D003596:Cytosine; D005260:Female; D005787:Gene Frequency; D006801:Humans; D007375:Interleukin-1 / Q000235:genetics*; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D010518:Periodontitis / Q000235:genetics*; D016133:Polymerase Chain Reaction; D020641:Polymorphism, Single Nucleotide; D011795:Surveys and Questionnaires; D013941:Thymine
chemical_list: D007375:Interleukin-1; D003596:Cytosine; D013941:Thymine