PTPN22 and rheumatoid arthritis: Figure 1 shows the loci shared between GWAS of ADs. The regions shared across the largest number of ADs include IL2RA (MS, T1D, RA, VI, AA and CD), IL23R (CD, UC, PS, BeD and AS), OLIG3/TNFAIP3 (RA, PS, SLE, UC, and CelD), PTPN22 (CD, RA, T1D, and VI), IL10 (CD, T1D, UC, and BeD), and an intergenic region between ZPBP2 and GSDMB (CD, RA, UC, and T1D).