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Item does not contain fulltext OBJECTIVE: In many rheumatoid arthritis (RA) patients, disease is controlled with anti-tumor necrosis factor (anti-TNF) biologic therapies. However, in a significant number of patients, the disease fails to respond to anti-TNF therapy. We undertook the present study to examine the hypothesis that rare and low-frequency genetic variants might influence response to anti-TNF treatment. METHODS: We sequenced the coding region of 750 genes in 1,094 RA patients of European ancestry who were treated with anti-TNF. After quality control, 690 genes were included in the analysis. We applied single-variant association and gene-based association tests to identify variants associated with anti-TNF treatment response. In addition, given the key mechanistic role of TNF, we performed gene set analyses of 27 TNF pathway genes. RESULTS: We identified 14,420 functional variants, of which 6,934 were predicted as nonsynonymous 2,136 of which were further predicted to be "damaging." Despite the fact that the study was well powered, no single variant or gene showed study-wide significant association with change in the outcome measures disease activity or European League Against Rheumatism response. Intriguingly, we observed 3 genes, of 27 with nominal signals of association (P < 0.05), that were involved in the TNF signaling pathway. However, when we performed a rigorous gene set enrichment analysis based on association P value ranking, we observed no evidence of enrichment of association at genes involved in the TNF pathway (Penrichment = 0.15, based on phenotype permutations). CONCLUSION: Our findings suggest that rare and low-frequency protein-coding variants in TNF signaling pathway genes or other genes do not contribute substantially to anti-TNF treatment response in patients with RA.

Supplemental Digital Content is available in the text, Celiac disease (CD) is common in Caucasians, but thought to be rare in Asians. Our aim was to determine the prevalence of CD in Chinese patients with chronic diarrhea predominant irritable bowel syndrome (IBS-D). From July 2010 to August 2012, 395 adult patients with IBS-D and 363 age and sex-matched healthy controls were recruited in Zhongnan Hospital of Wuhan University and Xiaogan Central Hospital in Hubei province, central China. Patients with IBS-D were diagnosed according to the Rome III criteria. Serum Immunoglobulin (IgA/IgG) anti-human tissue transglutaminase (anti-htTG)-deamidated gliadin peptide (DGP) antibodies were measured in a single ELISA (QUANTA Lite h-tTG/DGP Screen). Upper endoscopy with duodenal biopsies and HLA-DQA1 and HLA-DQB1 genotyping were performed in seropositive subjects and a gluten-free diet was prescribed. Seven IBS-D patients (7/395, 1.77%) and 2 healthy controls (2/363, 0.55%), were positive for anti-htTG/DGP antibodies. Of these 9 cases, 1 was lost to follow-up, 3 were suspected to have CD and 5 were eventually diagnosed as CD with intestinal histological lesions classified as Marsh Type II in 2 and Type III in 3. Of these 5 diagnosed CD patients, 4 (4/395, 1.01%) were from the IBS-D group and 1 (1/363, 0.28%) from the healthy control had asymptomatic CD. Two Type III CD patients with relatively high titers in the serologic assay were homozygous and heterozygous for haplotype HLA-DQA1∗03-DQB1∗03:03 (HLA-DQ9.3), respectively. In the present study, CD was present in 1.01% of patients with IBS-D and in 0.28% of the control group. We like to suggest that the haplotype HLA-DQA1∗03-DQB1∗03:03 (HLA-DQ9.3), which is common in Chinese, is a new susceptibility factor for CD in China. Larger screening and genetic studies are needed in the Chinese population of different regions.