TRAF1 and rheumatoid arthritis: In our study, further eQTL analysis, SMR analysis and differential expression analysis confirmed that some RNAm-SNPs were associated with gene expression levels in blood cells and that the gene expression levels were associated with RA, including the expression levels of PADI2, TRAF1, HLA-A, HLA-DRB1, HLA-DPB1 and HLA-B.