Human Th17 cells have been suggested to be involved in diseases such as multiple sclerosis [31] or juvenile idiopathic arthritis [32], but have been described to differ in certain aspects from their murine counterparts, e.g. human Th17 cells co-express IFN-γ more often than murine Th17 cells [33]. This evidence concerns the gene IFNG and juvenile idiopathic arthritis.