TNFAIP3 and rheumatoid arthritis: We analyzed the A20 expression level in cDNA samples from 38 RA patients and 40 healthy individuals by real-time PCR, and a significantly lower A20 expression level (5.96 ± 4.82) was found compared with that in healthy individuals (34.54 ± 26.89) (p < 0.001) (Figure 4).