Summary Background Anti‐tumor necrosis factor‐α (TNF‐α) is used for the treatment of severe cases of IBD, including Crohn's disease (CD) and ulcerative colitis (UC). However, one‐third of the patients do not respond to the treatment. We have previously investigated whether single nucleotide polymorphisms (SNPs) in genes involved in inflammation were associated with response to anti‐TNF therapy among patients with CD or UC. Aim A new cohort of patients was established for replication of the previous findings and to identify new SNPs associated with anti‐TNF response. Methods Fifty‐three SNPs assessed previously in cohort 1 (482 CD and 256 UC patients) were genotyped in cohort 2 (587 CD and 458 UC patients). The results were analysed using logistic regression (adjusted for age and gender). Results Ten SNPs were associated with anti‐TNF response either among patients with CD (TNFRSF1A(rs4149570) (OR: 1.92, 95% CI: 1.02‐3.60, P = 0.04), IL18(rs187238) (OR: 1.35, 95% CI: 1.00‐1.82, P = 0.05), and JAK2(rs12343867) (OR: 1.35, 95% CI: 1.02‐1.78, P = 0.03)), UC (TLR2(rs11938228) (OR: 0.55, 95% CI: 0.33‐0.92, P = 0.02), TLR4(rs5030728) (OR: 2.23, 95% CI: 1.24‐4.01, P = 0.01) and (rs1554973) (OR: 0.49, 95% CI: 0.27‐0.90, P = 0.02), NFKBIA(rs696) (OR: 1.45, 95% CI: 1.06‐2.00, P = 0.02), and NLRP3(rs4612666) (OR: 0.63, 95% CI: 0.44‐0.91, P = 0.01)) or in the combined cohort of patient with CD and UC (IBD) (TLR4(rs5030728) (OR: 1.46, 95% CI: 1.01‐2.11, P = 0.04) and (rs1554973)(OR: 0.80, 95% CI: 0.65‐0.98, P = 0.03), NFKBIA(rs696) (OR: 1.25, 95% CI: 1.01‐1.54, P = 0.04), NLRP3(rs4612666) (OR: 0.73, 95% CI: 0.57‐0.95, P = 0.02), IL1RN(rs4251961) (OR: 0.81, 95% CI: 0.66‐1.00, P = 0.05), IL18(rs1946518) (OR: 1.24, 95% CI: 1.01‐1.53, P = 0.04), and JAK2(rs12343867) (OR: 1.24, 95% CI: 1.01‐1.53, P = 0.04)). Conclusions The results support that polymorphisms in genes involved in the regulation of the NFκB pathway (TLR2, TLR4, and NFKBIA), the TNF‐α signalling pathway (TNFRSF1A), and other cytokine pathways (NLRP3, IL1RN, IL18, and JAK2) were associated with response to anti‐TNF therapy. Our multi‐SNP model predicted response rate of more than 82% (in 9% of the CD patients) and 75% (in 15% of the UC patients), compared to 71% and 64% in all CD and UC patients, respectively. More studies are warranted to predict response for use in the clinic.

BackgroundAnkylosing spondylitis (AS) results from the combined effects of susceptibility genes and environmental factors. Polymorphisms in genes regulating inflammation may explain part of the heritability of AS.MethodsUsing a candidate gene approach in this case-control study, 51 mainly functional single nucleotide polymorphisms (SNPs) in genes regulating inflammation were assessed in 709 patients with AS and 795 controls. Data on the patients with AS were obtained from the DANBIO registry where patients from all of Denmark are monitored in routine care during treatment with conventional and biologic disease modifying anti-rheumatic drugs (bDMARDs).The results were analyzed using logistic regression (adjusted for age and sex).ResultsNine polymorphisms were associated with risk of AS (p < 0.05). The polymorphisms were in genes regulating a: the TNF-α pathway (TNF -308 G > A (rs1800629), and − 238 G > A (rs361525); TNFRSF1A -609 G > T (rs4149570), and PTPN22 1858 G > A (rs2476601)), b: the IL23/IL17 pathway (IL23R G > A (rs11209026), and IL18–137 G > C (rs187238)), or c: the NFkB pathway (TLR1 743 T > C (rs4833095), TLR4 T > C (rs1554973), and LY96–1625 C > G (rs11465996)).After Bonferroni correction the homozygous variant genotype of TLR1 743 T > C (rs4833095) (odds ratios (OR): 2.59, 95% confidence interval (CI): 1.48–4.51, p = 0.04), and TNFRSF1A -609 G > T (rs4149570) (OR: 1.79, 95% CI: 1.31–2.41, p = 0.01) were associated with increased risk of AS and the combined homozygous and heterozygous variant genotypes of TNF -308 G > A (rs1800629) (OR: 0.56, 95% CI: 0.44–0.72, p = 0.0002) were associated with reduced risk of AS.ConclusionWe replicated associations between AS and the polymorphisms in TNF (rs1800629), TNFRSF1A (rs4149570), and IL23R (rs11209026). Furthermore, we identified novel risk loci in TNF (rs361525), IL18 (rs187238), TLR1 (rs4833095), TLR4 (rs1554973), and LY96 (rs11465996) that need validation in independent cohorts. The results suggest that genetically determined high activity of the TNF-α, IL23/IL17, and NFkB pathways increase risk of AS.

Highlights d A framework for investigating fasting-feeding cycles and circadian rhythms d Time-series analysis shows molecular oscillations are set by fasting-feeding cycles d In-depth lipidomics provides insights into metabolic crosstalk between tissues d Diurnal regulation of the hepatic PE methylation pathway and lipoprotein secretion

ObjectivesTo find causal genes for rheumatoid arthritis (RA) and its seropositive (RF and/or ACPA positive) and seronegative subsets.MethodsWe performed a genome-wide association study (GWAS) of 31 313 RA cases (68% seropositive) and ~1 million controls from Northwestern Europe. We searched for causal genes outside the HLA-locus through effect on coding, mRNA expression in several tissues and/or levels of plasma proteins (SomaScan) and did network analysis (Qiagen).ResultsWe found 25 sequence variants for RA overall, 33 for seropositive and 2 for seronegative RA, altogether 37 sequence variants at 34 non-HLA loci, of which 15 are novel. Genomic, transcriptomic and proteomic analysis of these yielded 25 causal genes in seropositive RA and additional two overall. Most encode proteins in the network of interferon-alpha/beta and IL-12/23 that signal through the JAK/STAT-pathway. Highlighting those with largest effect on seropositive RA, a rare missense variant in STAT4 (rs140675301-A) that is independent of reported non-coding STAT4-variants, increases the risk of seropositive RA 2.27-fold (p=2.1×10−9), more than the rs2476601-A missense variant in PTPN22 (OR=1.59, p=1.3×10−160). STAT4 rs140675301-A replaces hydrophilic glutamic acid with hydrophobic valine (Glu128Val) in a conserved, surface-exposed loop. A stop-mutation (rs76428106-C) in FLT3 increases seropositive RA risk (OR=1.35, p=6.6×10−11). Independent missense variants in TYK2 (rs34536443-C, rs12720356-C, rs35018800-A, latter two novel) associate with decreased risk of seropositive RA (ORs=0.63–0.87, p=10−9–10−27) and decreased plasma levels of interferon-alpha/beta receptor 1 that signals through TYK2/JAK1/STAT4.ConclusionSequence variants pointing to causal genes in the JAK/STAT pathway have largest effect on seropositive RA, while associations with seronegative RA remain scarce.