This result is in some agreement with that reported in another paper, which reports that CXCR5 cg04537602 locus methylation levels differ significantly between healthy individuals and patients with undifferentiated arthritis, and that a large proportion of patients with undifferentiated arthritis progress to RA, suggesting that CXCR5 methylation may be involved in the pathogenesis of RA.31 Here, CXCR5 is linked to rheumatoid arthritis.