Results from the analysis of DNA methylation patterns using Illumina HumanMethylation450 arrays showed no substantial differences between CD4+ T cells from 56 patients with oligoarticular juvenile idiopathic arthritis (JIA) and CD4+ T cells from 57 age-matched healthy individuals. The authors of the study suggest that this lack of a difference could indicate a less crucial role for epigenetic changes in JIA than in rheumatoid arthritis in adults.