PTPN2 and autoimmune disease: Based on the previously reported association between PTPN2 SNPs and different autoimmune diseases [14–26] and the scarcity of data about BD [5, 6], we investigated PTPN2 SNPs (rs2542151 T → G and rs7234029 A → G) in Egyptian patients with BD trying to find an association with disease susceptibility, phenotypic expression, and severity.