DNASE1 and rheumatoid arthritis: 2009), and reductions in plasma cf‐DNA in established rheumatoid arthritis (RA) patients, for example, (Dunaeva et al. 2015), which ruled out DNAse I as a mechanism of cf‐DNA decline. This study postulated a role for methotrexate drug treatment (reduced nucleotide metabolism and DNA synthesis), increased metabolism and ROS production by blood cells, increased oxidative enzyme activity (or decreased antioxidants), and the presence of novel cf‐DNA forms resulting from RA‐specific influences on apoptosis, cell shedding, or nucleosomes, in the reduction in cf‐DNA observed (Dunaeva et al. 2015).