IFNA2 and juvenile idiopathic arthritis: IFN-α2 concentrations were higher in jSLE (median 587 fg/ml, IQR 11–2744) as compared with JIA patients (median 7 fg/ml, IQR 3–236, P = 0.0017) and HCs (29 fg/ml, IQR 3–277; P = 0.017) (Fig. 1A, Supplementary Table S3, available at Rheumatology online), cross-sectionally.