title: Genetic variation on the BAT1-NFKBIL1-LTA region of major histocompatibility complex class III associates with periodontitis.
abstract: Periodontitis is a chronic inflammatory disease with a multifactorial etiology. We investigated whether human major histocompatibility complex (MHC) polymorphisms (6p21.3) are associated with periodontal parameters. Parogene 1 population samples (n = 169) were analyzed with 13,245 single nucleotide polymorphisms (SNPs) of the MHC region. Eighteen selected SNPs (P ≤ 0.001) were replicated in Parogene 2 population samples (n = 339) and the Health 2000 Survey (n = 1,420). All subjects had a detailed clinical and radiographic oral health examination. Serum lymphotoxin-α (LTA) concentrations were measured in the Parogene populations, and the protein was detected in inflamed periodontal tissue. In the Parogene 1 population, 10 SNPs were associated with periodontal parameters. The strongest associations emerged from the parameters bleeding on probing (BOP) and a probing pocket depth (PPD) of ≥6 mm with the genes BAT1, NFKBIL1, and LTA. Six SNPs, rs11796, rs3130059, rs2239527, rs2071591, rs909253, and rs1041981 (r(2), ≥0.92), constituted a risk haplotype. In the Parogene 1 population, the haplotype had the strongest association with the parameter BOP, a PPD of ≥6 mm, and severe periodontitis with odds ratios (95% confidence intervals) of 2.63 (2.21 to 3.20), 2.90 (2.37 to 3.52), and 3.10 (1.63 to 5.98), respectively. These results were replicated in the other two populations. High serum LTA concentrations in the Parogene population were associated with the periodontitis risk alleles of the LTA SNPs (rs909253 and rs1041981) of the haplotype. In addition, the protein was expressed in inflamed gingival connective tissue. We identified a novel BAT1-NFKBIL1-LTA haplotype as a significant contributor to the risk of periodontitis. The genetic polymorphisms in the MHC class III region may be functionally important in periodontitis susceptibility.
authors.affiliation: Institute of Dentistry, University of Helsinki, Helsinki, Finland.
authors.forename: K A Elisa
authors.initials: KA
authors.lastname: Kallio
authors.forename: Marja
authors.initials: M
authors.lastname: Marchesani
authors.forename: Efthymia
authors.initials: E
authors.lastname: Vlachopoulou
authors.forename: Päivi
authors.initials: P
authors.lastname: Mäntylä
authors.forename: Susanna
authors.initials: S
authors.lastname: Paju
authors.forename: Kåre
authors.initials: K
authors.lastname: Buhlin
authors.forename: Anna L
authors.initials: AL
authors.lastname: Suominen
authors.forename: Johanna
authors.initials: J
authors.lastname: Contreras
authors.forename: Matti
authors.initials: M
authors.lastname: Knuuttila
authors.forename: Marcela
authors.initials: M
authors.lastname: Hernandez
authors.forename: Sisko
authors.initials: S
authors.lastname: Huumonen
authors.forename: Markku S
authors.initials: MS
authors.lastname: Nieminen
authors.forename: Markus
authors.initials: M
authors.lastname: Perola
authors.forename: Juha
authors.initials: J
authors.lastname: Sinisalo
authors.forename: Marja-Liisa
authors.initials: ML
authors.lastname: Lokki
authors.forename: Pirkko J
authors.initials: PJ
authors.lastname: Pussinen
mesh_terms: D020022:Genetic Predisposition to Disease; D014644:Genetic Variation; D015894:Genome, Human; D006239:Haplotypes; D006306:Health Surveys; D049670:History, 17th Century; D049671:History, 18th Century; D006801:Humans; D008285:Major Histocompatibility Complex / Q000235:genetics* / Q000502:physiology*; D010518:Periodontitis / Q000235:genetics* / Q000276:immunology; D020641:Polymorphism, Single Nucleotide; D017434:Protein Structure, Tertiary