A major challenge in human genetics is to devise a systematic strategy to integrate disease-associated variants with diverse genomic and biological datasets to provide insight into disease pathogenesis and guide drug discovery for complex traits such as rheumatoid arthritis (RA)1. Here, we performed a genome-wide association study (GWAS) meta-analysis in a total of >100,000 subjects of European and Asian ancestries (29,880 RA cases and 73,758 controls), by evaluating ~10 million single nucleotide polymorphisms (SNPs). We discovered 42 novel RA risk loci at a genome-wide level of significance, bringing the total to 1012–4. We devised an in-silico pipeline using established bioinformatics methods based on functional annotation5, cis-acting expression quantitative trait loci (cis-eQTL)6, and pathway analyses7–9 – as well as novel methods based on genetic overlap with human primary immunodeficiency (PID), hematological cancer somatic mutations and knock-out mouse phenotypes – to identify 98 biological candidate genes at these 101 risk loci. We demonstrate that these genes are the targets of approved therapies for RA, and further suggest that drugs approved for other indications may be repurposed for the treatment of RA. Together, this comprehensive genetic study sheds light on fundamental genes, pathways and cell types that contribute to RA pathogenesis, and provides empirical evidence that the genetics of RA can provide important information for drug discovery.

With methotrexate, joint damage progresses even at low and moderate disease activity levels, whereas methotrexate plus infliximab inhibits radiographic progression across all disease activity states.

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Objective. A single-nucleotide polymorphism in the PTPN22 gene encoding the lymphoid protein tyrosine phosphatase (Lyp) has recently been identified as a functional variant associated with susceptibility to rheumatoid arthritis (RA), type 1 diabetes, and systemic lupus erythematosus. To determine whether association of this variant (PTPN22 1858T) with RA is reproducible and is also observed in another autoimmune condition, Crohn's disease, we investigated the association between the PTPN22 1858T allele and RA and Crohn's disease in a Canadian population.Methods. Two RA case-control cohorts representing a total of 1,234 patients and 791 healthy controls as well as a cohort of 455 patients with Crohn's disease and 190 controls were genotyped for the PTPN22 C1858T polymorphism, and genotype frequencies were compared between patients and controls.Results. Significant association of the PTPN22 1858T allele with RA was detected in both the Torontobased RA cohort (P ‫؍‬ 1.6 ؋ 10 ؊6 , odds ratio [OR] 1.8) and the Halifax-based RA cohort (P ‫؍‬ 9.4 ؋ 10 ؊4 , OR 1.94). Association of the risk allele with RA was not affected by sex, age at disease onset, or the presence of either rheumatoid factor or rheumatoid nodules. No association between the PTPN22 risk allele and Crohn's disease was detected.Conclusion. These observations confirm the association of RA susceptibility with the PTPN22 1858T allele. However, the data also reveal a lack of association between this variant and Crohn's disease, suggesting that the PTPN22 1858T allele is a risk allele for multiple, but not all, autoimmune diseases.Rheumatoid arthritis (RA) is one of the most common systemic autoimmune disorders, affecting an estimated 0.5-1% of the population. The disease is characterized by peripheral synovial joint inflammation, which leads to cartilage and bone damage and, ulti-

Biologics have changed expectation and outcomes for rheumatoid arthritis (RA). However, the optimal duration and sequence of therapy for this disease has yet to be determined. Also, a significant number of patients do not satisfactorily respond to currently available therapies. The Janus kinase (JAK) inhibitors represent a new class of therapies for RA. These drugs work uniquely by inhibiting intracellular pathways thought to be important in the pathogenesis of RA. They are available as oral agents, which is also different from the currently available biologics. Baricitinib has now been evaluated in four phase III clinical trials, and although safety concerns cannot fully be answered until the drug is studied over longer periods of time, the data to date suggest that this drug with its once daily dosing, rapid onset of action and efficacy as monotherapy represents an important addition to the RA therapeutic armamentarium. Further study and experience will better define how baricitinib will be used and by which patients.

Trans-ancestry genetic research promises to improve power to detect genetic signals, fine-mapping resolution, and performances of polygenic risk score (PRS). We here present a large-scale genome-wide association study (GWAS) of rheumatoid arthritis (RA) which includes 276,020 samples of five ancestral groups. We conducted a trans-ancestry meta-analysis and identified 124 loci (P < 5 × 10-8), of which 34 were novel. Candidate genes at the novel loci suggested essential roles of the immune system (e.g., TNIP2 and TNFRSF11A) and joint tissues (e.g., WISP1) in RA etiology. Trans-ancestry fine mapping identified putatively causal variants with biological insights (e.g., LEF1). Moreover, PRS based on trans-ancestry GWAS outperformed PRS based on single-ancestry GWAS and had comparable performance between European and East Asian populations. Our study provides multiple insights into the etiology of RA and improves genetic predictability of RA.

Comorbidity is common in early inflammatory arthritis and associated with higher disease activity, worse functional status and greater pain scores during the first year of follow-up. While the mechanisms for this association require investigation, addressing comorbidity may improve clinical outcomes in early RA.

14-3-3η autoantibodies, alone and in combination with the 14-3-3η protein, RF, and/or ACPA identified most patients with early RA.