title: Evaluation of RANK/RANKL/OPG gene polymorphisms in aggressive periodontitis.
abstract: OBJECTIVE
  Aggressive periodontitis (AgP) is a specific type of periodontal disease that is characterized by rapid attachment loss and bone destruction. While attempting to identify genetic polymorphisms associated with AgP, previous research has focused on candidate genes that may be involved in immune responses to microbial infections. In this study, the focus was on single nucleotide polymorphisms (SNPs) in the key mediators of osteoclast differentiation and activation, which involve receptor activator of nuclear factor-kappaB (RANK), RANK ligand (RANKL) and osteoprotegrin (OPG), in the Japanese population. The aim of this study was to evaluate the association of RANK/RANKL/OPG gene polymorphisms with AgP in the Japanese population.
  
  
  METHODS
  We examined 99 patients with AgP and 89 controls from the Japanese population to explore the possibility of RANK/RANKL/OPG loci as candidate regions associated with the disease. All exons and relevant exon-intron boundaries of these three candidate genes were amplified by polymerase chain reaction (PCR) using 19 primers, followed by direct sequencing. The polymorphisms were identified by comparing the sequences obtained from 48 subjects.
  
  
  RESULTS
  We identified 27 SNPs in RANK, including 10 novel SNPs and seven SNPs each in both RANKL and OPG. A pairwise linkage disequilibrium analysis using the r2 statistic showed that some SNP pairs from the three loci are in tight linkage disequilibrium.
  
  
  CONCLUSIONS
  An association analysis with allelotypes showed that SNPs identified in the RANK/RANKL/OPG genes have no significant association with AgP in the Japanese population.
authors.affiliation: Computational and Experimental Systems Biology Group, RIKEN, Genomic Sciences Center, RIKEN, Yokohama, Japan.
authors.forename: N
authors.initials: N
authors.lastname: Soedarsono
authors.forename: D
authors.initials: D
authors.lastname: Rabello
authors.forename: H
authors.initials: H
authors.lastname: Kamei
authors.forename: D
authors.initials: D
authors.lastname: Fuma
authors.forename: Y
authors.initials: Y
authors.lastname: Ishihara
authors.forename: M
authors.initials: M
authors.lastname: Suzuki
authors.forename: T
authors.initials: T
authors.lastname: Noguchi
authors.forename: Y
authors.initials: Y
authors.lastname: Sakaki
authors.forename: A
authors.initials: A
authors.lastname: Yamaguchi
authors.forename: T
authors.initials: T
authors.lastname: Kojima
mesh_terms: D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D016301:Alveolar Bone Loss / Q000235:genetics; D001483:Base Sequence; D016022:Case-Control Studies; D005260:Female; D005787:Gene Frequency; D006801:Humans; D007564:Japan; D015810:Linkage Disequilibrium; D008297:Male; D008875:Middle Aged; D010010:Osteoclasts / Q000473:pathology; D053244:Osteoprotegerin / Q000235:genetics*; D010518:Periodontitis / Q000235:genetics*; D016133:Polymerase Chain Reaction; D020641:Polymorphism, Single Nucleotide; D053245:RANK Ligand / Q000235:genetics*; D053246:Receptor Activator of Nuclear Factor-kappa B / Q000235:genetics*
chemical_list: D053244:Osteoprotegerin; D053245:RANK Ligand; D053246:Receptor Activator of Nuclear Factor-kappa B