title: Confirmation of association of IRGM and NCF4 with ileal Crohn's disease in a population-based cohort.
abstract: Genome-wide association studies have identified PHOX2B, FAM92B, IRGM and NCF4 as candidate susceptibility factors for ileal Crohn's disease (CD). Here we sought to determine whether these genes were also associated with ileal CD in New Zealand Caucasians, as well as with ileocolonic CD, colonic CD and ulcerative colitis (UC). A total of 507 CD patients, 475 UC patients and 576 controls were genotyped for the single nucleotide polymorphisms rs16853571 (PHOX2B), rs4821544 (NCF4), rs13361189 and rs4958847 (IRGM), and rs8050910 (FAM92B). NCF4 and IRGM were significantly associated with ileal CD (P-value(rs4821544)=0.0090, odds ratio (OR)=1.425, 95% confidence interval (CI): 1.092-1.859; P-value(rs13361189)=0.0017, OR=1.942, 95% CI: 1.274-2.959; P-value(rs4958847)=0.0022, OR=1.767, 95% CI: 1.224-2.558), but not with other forms of inflammatory bowel disease (IBD). No association of PHOX2B or FAM92B with IBD was detected. Our study has demonstrated that IRGM and NCF4 are ileal-specific CD susceptibility factors in New Zealand Caucasians.
authors.affiliation: Department of Pathology, University of Otago, Christchurch, New Zealand. rebecca.roberts@otago.ac.nz
authors.forename: R L
authors.initials: RL
authors.lastname: Roberts
authors.forename: J E
authors.initials: JE
authors.lastname: Hollis-Moffatt
authors.forename: R B
authors.initials: RB
authors.lastname: Gearry
authors.forename: M A
authors.initials: MA
authors.lastname: Kennedy
authors.forename: M L
authors.initials: ML
authors.lastname: Barclay
authors.forename: T R
authors.initials: TR
authors.lastname: Merriman
mesh_terms: D003424:Crohn Disease / Q000235:genetics*; D019204:GTP-Binding Proteins / Q000235:genetics*; D006801:Humans; D007077:Ileal Diseases / Q000235:genetics*; D008875:Middle Aged; D019255:NADPH Oxidases / Q000235:genetics*; D009520:New Zealand
chemical_list: D019255:NADPH Oxidases; C113333:NCF4 protein, human; D019204:GTP-Binding Proteins; C513539:IRGM protein, human