Little is known regarding differences in the gut microbiomes of rheumatoid arthritis (RA) patients and healthy cohorts in China. This study aimed to identify differences in the fecal microbiomes of 66 Chinese patients with RA and 60 healthy Chinese controls. The V3-V4 variable regions of bacterial 16S rRNA genes were sequenced with the Illumina system to define the bacterial composition. The alpha-diversity index of the microbiome of the RA patients was significantly lower than that of the control group. The bacterial genera Bacteroides (p = 0.02202) and Escherichia-Shigella (p = 0.03137) were more abundant in RA patients. In contrast, Lactobacillus (p = 0.000014), Alloprevotella (p = 0.0000008615), Enterobacter (p = 0.000005759), and Odoribacter (p = 0.0000166) were less abundant in the RA group than in the control group. Spearman correlation analysis of blood physiological measures of RA showed that bacterial genera such as Dorea and Ruminococcus were positively correlated with RF-IgA and anti-CCP antibodies. Furthermore, Alloprevotella and Parabacteroides were positively correlated with the erythrocyte sedimentation rate, and Prevotella-2 and Alloprevotella were positively correlated with C-reactive protein, both biomarkers of inflammation. These findings suggest that the gut microbiota may contribute to RA development via interactions with the host immune system.

Genome-wide association studies have identified more than 90 susceptibility loci for breast cancer. However, the missing heritability is evident, and the contributions of coding variants to breast cancer susceptibility have not yet been systematically evaluated. Here, we present a large-scale whole-exome association study for breast cancer consisting of 24,162 individuals (10,055 cases and 14,107 controls). In addition to replicating known susceptibility loci (e.g., , and), we identify two novel missense variants in (rs13047478, = 4.52 × 10) and (rs3810151, = 7.60 × 10) and one new noncoding variant at 7q21.11 ( < 5 × 10). and possessed functional roles in the control of breast cancer cell growth, and the two coding variants were found to be the eQTL for several nearby genes. rs13047478 was significantly ( < 5.00 × 10) associated with the expression of genes and in breast mammary tissues. rs3810151 was found to be significantly associated with the expression of genes ( = 8.39 × 10) and ( = 3.77 × 10) in human blood samples. and, together with these eQTL genes, were differentially expressed in breast tumors versus normal breast. Our study reveals additional loci and novel genes for genetic predisposition to breast cancer and highlights a polygenic basis of disease development. Large-scale genetic screening identifies novel missense variants and a noncoding variant as predisposing factors for breast cancer. .

Genome-wide association studies have identified &gt;100 genetic risk factors for rheumatoid arthritis. However, the reported genetic variants could only explain less than 40% heritability of rheumatoid arthritis. The majority of the heritability is still missing and needs to be identified with more studies with different approaches and populations. In order to identify novel function SNPs to explain missing heritability and reveal novel mechanism pathogenesis of rheumatoid arthritis, 4 HLA SNPs (HLA-DRB1, HLA-DRB9, HLA-DQB1, and TNFAIP3) and 225 common SNPs located in miRNA, which might influence the miRNA target binding or pre-miRNA stability, were genotyped in 1,607 rheumatoid arthritis and 1,580 matched normal individuals. We identified 2 novel SNPs as significantly associated with rheumatoid arthritis including rs1414273 (miR-548ac, OR = 0.84, p = 8.26 × 10−4) and rs2620381 (miR-627, OR = 0.77, p = 2.55 × 10−3). We also identified that rs5997893 (miR-3928) showed significant epistasis effect with rs4947332 (HLA-DRB1, OR = 4.23, p = 0.04) and rs2967897 (miR-5695) with rs7752903 (TNFAIP3, OR = 4.43, p = 0.03). In addition, we found that individuals who carried 8 risk alleles showed 15.38 (95%CI: 4.69–50.49, p &lt; 1.0 × 10−6) times more risk of being affected by RA. Finally, we demonstrated that the targets of the significant miRNAs showed enrichment in immune related genes (p = 2.0 × 10−5) and FDA approved drug target genes (p = 0.014). Overall, 6 novel miRNA SNPs including rs1414273 (miR-548ac, p = 8.26 × 10−4), rs2620381 (miR-627, p = 2.55 × 10−3), rs4285314 (miR-3135b, p = 1.10 × 10−13), rs28477407 (miR-4308, p = 3.44 × 10−5), rs5997893 (miR-3928, p = 5.9 × 10−3) and rs45596840 (miR-4482, p = 6.6 × 10−3) were confirmed to be significantly associated with RA in a Chinese population. Our study suggests that miRNAs might be interesting targets to accelerate understanding of the pathogenesis and drug development for rheumatoid arthritis.

ObjectiveAlthogh Genome-wide association studies have identified >100 variants for rheumatoid arthritis (RA),the reported genetic variants only explain <40% of RA heritability. We conducted a systemic association study between common East-Asian miRNA SNPs with RA in a large Han Chinese cohort to explain missing heritability and identify miRNA epistatic interactions.Methods4 HLA SNPs (HLA-DRB1, HLA-DRB9, HLA-DQB1 and TNFAIP3) and 225 common SNPs located in miRNA which might influence the miRNA target binding or pre-miRNA stability were genotyped in 1,607 rheumatoid arthritis and 1,580 matched normal individuals. A meta-analysis with previous GWAS studies (4,873 RA cases and 17,642 controls) was performed to discovery another novel miRNA RA-associated SNPs.Results2 novel SNPs including rs1414273 (miR-548ac, OR=0.84, P=8.26×10-4) and rs2620381 (miR-627, OR=0.77, P=2.55×10-3) conferred significant association with RA. Individuals carried 8 risk alleles showed 15.38 (95%CI: 4.69-50.49, P<1.0×10-6) times more risk to be affected by RA. In addition, rs5997893 (miR-3928) showed significant epistasis effect with rs4947332 (HLA-DRB1, OR=4.23, P=0.04) and rs2967897 (miR-5695) with rs7752903 (TNFAIP3, OR=4.43, P=0.03). Finally, we demonstrated targets of the significant miRNAs showed enrichment in immune related genes (P=2.0×10-5) and FDA approved drug target genes (P=0.014).Conclusions6 novel miRNA SNPs including rs1414273 (miR-548ac, P=8.26×10-4), rs2620381 (miR-627, P=2.55×10-3), rs4285314 (miR-3135b, P=1.10×10-13), rs28477407 (miR-4308, P=3.44×10-5), rs5997893 (miR-3928, P=5.9×10-3) and rs45596840 (miR-4482, P=6.6×10-3) were confirmed to be significantly associated with RA in a Chinese population. Our study suggests that miRNAs might be interesting targets to accelerate the understanding of the pathogenesis and drug development for rheumatoid arthritis.