Abstract
BackgroundTo investigate the association between 12 single nucleotide polymorphisms (SNPs) located on ERAP1 and IL23R with the presence of inflammation on the sacroiliac joint (SIJ) or spinal magnetic resonance imagery (MRI) in an early onset spondyloarthritis (SpA) cohort.MethodsAll the patients included in the DESIR cohort with an axial SpA and available DNA at baseline were enrolled in this study (n = 645 patients) and underwent a clinical examination, CRP assay, SIJ and spinal MRI scans. Six SNPs located on ERAP1 (rs30187, rs27044, rs27434, rs17482078, rs10050860, rs2287987) and six SNPs located on IL23R (rs1004819, rs10489629, rs1343151, rs2201841, rs10889677, rs11209032) were genotyped. Univariable analyses were performed to test the association between the genotypes and SIJ and spinal MRI inflammation, as well as disease activity based on Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Ankylosing Spondylitis Disease Activity Score-C-Reactive Protein (ASDAS-CRP) and CRP.ResultsOne SNP located on ERAP1 (rs27434) and haplotype CCT of ERAP1 were associated with SIJ inflammation detected by MRI, but these associations were below the Bonferroni corrected threshold of significance. However, one SNP (rs1004819) located on IL23R was associated with SIJ MRI inflammation (rs1004819: TT 42.3%, CT 40.5%, CC 26.5%, p = 0.0005). This locus was also significantly associated with Spondyloarthritis Research Consortium of Canada scores while no association with another inflammatory parameter such as BASDAI, ASDAS-CRP, CRP or Berlin MRI score was identified in this population.ConclusionOne locus of the IL23R gene was associated with SIJ MRI inflammation and might be a marker of more active disease in recent onset SpA.Trial registrationclinicaltrials.gov, NCTO 164 8907
Highlights
To investigate the association between 12 single nucleotide polymorphisms (SNPs) located on ERAP1 and IL23R with the presence of inflammation on the sacroiliac joint (SIJ) or spinal magnetic resonance imagery (MRI) in an early onset spondyloarthritis (SpA) cohort
Other genes are involved in the genetic background for SpA since Human leucocyte antigen (HLA)-B27 is detected in around 90% of patients with ankylosing spondylitis (AS) and in 30–50% of cases involving other SpA subtypes such as psoriatic arthritis (PsA) or SpA associated with inflammatory bowel disease [2]
Two Single nucleotide polymorphism (SNP) located on the IL23R gene showed strong linkage disequilibrium (r2 2 = 0.96, D′ = 1), and a haplotype including these two loci was created and used for further analyses
Summary
To investigate the association between 12 single nucleotide polymorphisms (SNPs) located on ERAP1 and IL23R with the presence of inflammation on the sacroiliac joint (SIJ) or spinal magnetic resonance imagery (MRI) in an early onset spondyloarthritis (SpA) cohort. Other genes are involved in the genetic background for SpA since HLA-B27 is detected in around 90% of patients with ankylosing spondylitis (AS) and in 30–50% of cases involving other SpA subtypes such as psoriatic arthritis (PsA) or SpA associated with inflammatory bowel disease [2]. Several genome-wide association (GWA) studies have been published on AS susceptibility in individuals from European and Asian populations, which have identified at least 31 significant non-HLA genetic loci. These genes account for up to 25% of the overall heritability of AS, with the overwhelming majority provided by HLA-B27 per se [2, 3]. Among these recently identified loci, variations within genes encoding proteins involved in interferon or tumour necrosis factor/NFkB signalling and transcription have been identified, as well as genes influencing IL-23/IL-17 signalling or TCD8+ differentiation or genes encoding proteins crucial for antigen presentation [3]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
