KRT1 and Harlequin ichthyosis: However, other subtypes of ichthyoses, that is, harlequin ichthyosis caused by ABCA12 mutations, Netherton syndrome caused by SPINK5 mutations and epidermolytic ichthyosis caused by KRT1 or KRT10 mutations show increased prevalences of secondary skin infections, which can be attributed both to a more severe barrier failure and to distinctive abnormalities in the lamellar bodies secretory system that collectively decrease the bioavailability of AMPs.26