PDCD1 and Behcet disease: The PDCD1 SNPs, termed PD‐1.3 (rs11568821), PD‐1.5 (rs2227981), PD‐1.6 (rs10204525) and PD‐1.7 (rs7421861), had a MAF ≥0.05 in the reported Toscani population in Italy as well as in BD (Table S1).