The so-called IFN signature refers to the evidence of an upregulation of transcripts induced by the different IFN subtypes.17,19 Until recently, the term did not allow differentiation between the three families of IFNs, whereas in recent literature both the terms “IFN signature” and “type I IFN signature” are used to encompass the overexpression of genes induced by type I IFNs.18,20 Diseases in which this signature appears to play a prominent role are SLE, Sjögren’s syndrome, inflammatory myositis and scleroderma.17,19,21–24. Here, IFNA1 is linked to systemic lupus erythematosus.