Furthermore, an epigenome-wide study of monozygotic twins discordant for RA found that DMARD treatment led to hypomethylation of the promoter of Ring finger protein 5 (RNF5) and 1-acyl-sn-glycerol-3-phosphate acyltransferase alpha (AGPAT1) genes that have been implicated in inflammation and autoimmunity [72]. Here, RNF5 is linked to rheumatoid arthritis.