KRT5 and epidermolysis bullosa simplex: In support of the latter, small, dominantly acting missense variants affecting the polymerization and mechanical properties of either K5 or K14 are causative for epidermolysis bullosa simplex (EBS), a rare genetic skin disorder in which basal layer keratinocytes are fragile and shear or lyse in response to trauma (Bonifas et al., 1991; Coulombe et al., 1991; Coulombe et al., 2009).