Consequently, a GWAS including 388 children with JIA cases and 2500 controls with European ancestry replicated three previously reported loci mapped to the genes PTPN22, IL2RA, and ANTXR2. Besides, they identified a novel locus with the peak SNP (rs953387), an expression quantitative trait locus (eQTL) associated with the expression level of CXCR4 in T-cells (p = 0.0054) and lymphoblastoid cells (p = 0.014) [68]. This evidence concerns the gene PTPN22 and juvenile idiopathic arthritis.