Data showed that although the mRNA expression of METTL3, METTL14, and WTAP was unchanged (all P > 0.050) (Figures 1(a)–1(c)), the mRNA expression of ALKBH5, FTO, and YTHDF2 in the peripheral blood was significantly decreased in RA patients compared to CON (all P < 0.050) (Figures 1(d)–1(f)). Here, YTHDF2 is linked to rheumatoid arthritis.