Transcriptomic Analysis of the Major Orphan Ichthyosis Subtypes Reveals Shared Immune and Barrier Signatures

In this study we performed the first global RNA-seq analysis in 54 ichthyosis patients (7 Netherton syndrome/NS, 13 epidermolytic ichthyosis/EI, 16 lamellar ichthyosis/LI, 18 congenital ichthyosiform erythroderma/CIE) and 40 healthy controls. Differentially expressed genes (DEGs) were defined based on fold changes/FCH>2 and false discovery rate/FDR<0.05 criteria. We found robust and significant Th22/Th17 skewing in all subtypes (e.g. IL-17A/C/F, S100A7/8/9/12; p<0.001) with modest changes in Th2 pathway, primarily in NS, and Th1 skewing in CIE. RNA-seq data was profiled from skin biopsies of 54 ichthyosis patients (7 Netherton syndrome/NS, 13 epidermolytic ichthyosis/EI, 16 lamellar ichthyosis/LI, 18 congenital ichthyosiform erythroderma/CIE) and 40 healthy controls.