title: Confirmation of TNIP1 and IL23A as susceptibility loci for psoriatic arthritis.
abstract: OBJECTIVE
  To investigate a shared genetic aetiology for skin involvement in psoriasis and psoriatic arthritis (PsA) by genotyping single-nucleotide polymorphisms (SNPs), reported to be associated in genome-wide association studies of psoriasis, in patients with PsA.
  
  
  METHODS
  SNPs with reported evidence for association with psoriasis were genotyped in a PsA case and control collection from the UK and Ireland. Genotype and allele frequencies were compared between PsA cases and controls using the Armitage test for trend.
  
  
  RESULTS
  Seven SNPs mapping to the IL1RN, TNIP1, TNFAIP3, TSC1, IL23A, SMARCA4 and RNF114 genes were successfully genotyped. The IL23A and TNIP1 genes showed convincing evidence for association (rs2066808, p = 9.1×10(-7); rs17728338, p = 3.5×10(-5), respectively) whilst SNPs mapping to the TNFAIP3, TSC1 and RNF114 genes showed nominal evidence for association (rs610604, p = 0.03; rs1076160, p = 0.03; rs495337, p = 0.0025). No evidence for association with IL1RN or SMARCA4 was found but the power to detect association was low.
  
  
  CONCLUSIONS
  SNPs mapping to previously reported psoriasis loci show evidence for association to PSA, thus supporting the hypothesis that the genetic aetiology of skin involvement is the same in both PsA and psoriasis.
authors.affiliation: Arthritis Research UK Epidemiology Unit, Manchester Academic Health Science Centre, The University of Manchester, Manchester, UK.
authors.forename: John
authors.initials: J
authors.lastname: Bowes
authors.forename: Gisela
authors.initials: G
authors.lastname: Orozco
authors.forename: Edward
authors.initials: E
authors.lastname: Flynn
authors.forename: Pauline
authors.initials: P
authors.lastname: Ho
authors.forename: Rasha
authors.initials: R
authors.lastname: Brier
authors.forename: Helena
authors.initials: H
authors.lastname: Marzo-Ortega
authors.forename: Laura
authors.initials: L
authors.lastname: Coates
authors.forename: Ross
authors.initials: R
authors.lastname: McManus
authors.forename: Anthony W
authors.initials: AW
authors.lastname: Ryan
authors.forename: David
authors.initials: D
authors.lastname: Kane
authors.forename: Eleanor
authors.initials: E
authors.lastname: Korendowych
authors.forename: Neil
authors.initials: N
authors.lastname: McHugh
authors.forename: Oliver
authors.initials: O
authors.lastname: FitzGerald
authors.forename: Jonathan
authors.initials: J
authors.lastname: Packham
authors.forename: Ann W
authors.initials: AW
authors.lastname: Morgan
authors.forename: Ian N
authors.initials: IN
authors.lastname: Bruce
authors.forename: Anne
authors.initials: A
authors.lastname: Barton
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D015535:Arthritis, Psoriatic / Q000235:genetics*; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D004268:DNA-Binding Proteins / Q000235:genetics*; D005260:Female; D005787:Gene Frequency; D056426:Genetic Loci; D020022:Genetic Predisposition to Disease; D055106:Genome-Wide Association Study; D005838:Genotype; D006801:Humans; D053760:Interleukin-23 Subunit p19 / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide; D011565:Psoriasis / Q000235:genetics; D055815:Young Adult
chemical_list: D004268:DNA-Binding Proteins; C508840:IL23A protein, human; D053760:Interleukin-23 Subunit p19; C117046:TNIP1 protein, human