An early success of GWAS in pediatric rheumatic diseases was the discovery of VTCN1, implicated in immune attenuation through B/T lymphocytes, as a novel JIA susceptibility locus in a 2009 study involving 279 JIA cases in the discovery cohort and 321 JIA cases in the validation cohort (7). Here, VTCN1 is linked to juvenile idiopathic arthritis.