We identified the soluble receptor for advanced glycation end products (sRAGE), a critical inflammatory pathway protein, as putatively causal and protective for both RA (odds ratio per 1-standard deviation increment in inverse-rank normalized sRAGE level = 0.364; 95% confidence interval 0.342–0.385; P = 6.40 × 10–241) and RF levels (β [change in RF level per sRAGE increment] = − 1.318; SE = 0.434; P = 0.002). This evidence concerns the gene AGER and rheumatoid arthritis.