Sustained DMARD-free remission (SDFR; sustained absence of synovitis after DMARD discontinuation) is prevalent within ACPA-negative RA (~ 40%), but conversely, other ACPA-negative RA patients have persisting disease, generally requiring life-long disease-modifying antirheumatic drugs (DMARDs) [3]. This evidence concerns the gene PRTN3 and rheumatoid arthritis.