One of the most definitive genome-wide association studies in pSS patients identified single nucleotide polymorphisms in many IFN-inducible genes that are implicated in innate immunity, specifically HLA-alleles, STAT4, IRF5, IL-12A and TNIP1.4 Bodewes et al. assessed the relationship between systemic IFN type I and II activity and disease manifestations in pSS and they showed that systemic IFN activation is associated with higher activity only in the ESSDAI biological domain but not in the other domains or the total score. Here, IRF5 is linked to peeling skin syndrome.