Interestingly, transgenic mice overexpressing Ela2 also exhibit a barrier defect, which probably results from excessive (pro-)filaggrin processing combined with alterations in lipid metabolism; similar changes in lipid metabolism are seen in the skin of Netherton syndrome patients (Bonnart et al., 2010; Fartasch et al., 1999; van Smeden et al., 2014). Here, FLG is linked to Netherton syndrome.