title: Association study in Romanians confirms IL23A gene haplotype block rs2066808/rs11171806 as conferring risk to psoriatic arthritis.
abstract: BACKGROUND
  The cytokines IL12 and IL23 have been recently implicated in the pathogenesis of psoriatic arthritis (PsA). In this study we investigated the genetic variations in the genes coding for IL12, IL23 and IL23 receptor as a plausible source of susceptibility and modification of clinical symptoms of PsA in Romanian population.
  
  
  METHODS
  Twenty five SNPs mapping to IL12A, IL12B, IL23A, IL23R and IL12RB1 genes were genotyped in 94 PsA patients and 161 healthy controls of Romanian ethnicity using the Sequenom genotyping platform.
  
  
  RESULTS
  The exonic SNP rs11171806 from IL23A gene was significantly underrepresented in patients versus controls (p=0.03, OR 0.391) and the carriers of rs11171806/rs2066808 AC haplotype had decreased risk for PsA (p=0.03). The two SNPs of the highly conserved gene IL23A are in complete LD in our population. Genetic variants of IL12B gene were associated with polyarticular subtype of PsA. No associations were found between SNPs from IL12A, IL23R and IL12RB1 genes and susceptibility to PsA and its phenotypes.
  
  
  CONCLUSIONS
  We confirm the previously described association of rs2066808 variant with psoriasis and PsA and we show evidence of an extended genomic region inside IL23A gene as carrier of true disease susceptibility factors. These data suggest a role for IL23 in the PsA pathogenesis in Romanians.
authors.affiliation: Department of Immunology and Pathophysiology, Faculty of Medicine, University "Carol Davila", Bucharest, Romania; Laboratory of Immunogenomics and Immunoproteomics, Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacky University, Olomouc, Czech Republic. Electronic address: oliviapopa@yahoo.com.
authors.forename: Olivia Mihaela
authors.initials: OM
authors.lastname: Popa
authors.affiliation: Laboratory of Immunogenomics and Immunoproteomics, Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacky University, Olomouc, Czech Republic. Electronic address: eva.kriegova@email.cz.
authors.forename: Eva
authors.initials: E
authors.lastname: Kriegova
authors.affiliation: Molecular Biology Department, Grigore Antipa National Museum of Natural History, Bucharest, Romania. Electronic address: popaluis@antipa.ro.
authors.forename: Luis
authors.initials: L
authors.lastname: Popa
authors.affiliation: Laboratory of Immunogenomics and Immunoproteomics, Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacky University, Olomouc, Czech Republic. Electronic address: Petra.Schneiderova@fnol.cz.
authors.forename: Petra
authors.initials: P
authors.lastname: Schneiderova
authors.affiliation: National Institute of Blood Transfusion, Bucharest, Romania. Electronic address: monica_dutescu@yahoo.com.
authors.forename: Monica Irina
authors.initials: MI
authors.lastname: Dutescu
authors.affiliation: Department of Rheumatology, Faculty of Medicine, University "Carol Davila", "I.C. Cantacuzino" Hospital, Bucharest, Romania. Electronic address: vmbojinca@yahoo.com.
authors.forename: Mihai
authors.initials: M
authors.lastname: Bojinca
authors.affiliation: Department of Immunology and Pathophysiology, Faculty of Medicine, University "Carol Davila", Bucharest, Romania. Electronic address: caravi.bara@gmail.com.
authors.forename: Constantin
authors.initials: C
authors.lastname: Bara
authors.affiliation: Laboratory of Immunogenomics and Immunoproteomics, Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacky University, Olomouc, Czech Republic. Electronic address: martin.petrek@fnol.cz.
authors.forename: Martin
authors.initials: M
authors.lastname: Petrek
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015535:Arthritis, Psoriatic / Q000235:genetics* / Q000473:pathology; D016022:Case-Control Studies; D005260:Female; D005787:Gene Frequency / Q000235:genetics; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease; D006239:Haplotypes / Q000235:genetics*; D006801:Humans; D053765:Interleukin-12 Subunit p35 / Q000235:genetics; D053760:Interleukin-23 Subunit p19 / Q000235:genetics*; D015810:Linkage Disequilibrium / Q000235:genetics; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D018123:Receptors, Interleukin / Q000235:genetics; D012307:Risk Factors; D012383:Romania; D055815:Young Adult
chemical_list: C508858:IL12A protein, human; C508840:IL23A protein, human; C515500:IL23R protein, human; D053765:Interleukin-12 Subunit p35; D053760:Interleukin-23 Subunit p19; D018123:Receptors, Interleukin