The minor allele (T) at 1858C>T (rs2476601) single-nucleotide polymorphism (SNP) in the protein tyrosine phosphatase non-receptor type 22 (PTPN22, gene map locus 1p13) gene has been extensively associated with susceptibility to various autoimmune diseases [2]. The gene discussed is PTPN22; the disease is autoimmune disease.