Upregulation of IL-17 was also found in ASD children with concomitant asthma [66,67], while the IL-23 cytokine, known to induce Th17 cell secretion of IL-17, was inversely found to be down-regulated in children at ASD onset, although it was positively associated with more impaired behavioral scores [54,69]. The gene discussed is IL17A; the disease is asthma.