"Nails Only" Phenotype and Partial Dominance of p.Glu170Lys Mutation in a Family with Epidermolysis Bullosa Simplex.

Epidermolysis bullosa (EB) is a heterogeneous group of rare, chronic, inherited skin disorders characterized by marked mechanical fragility of epithelial tissues, with blistering and erosions after minor trauma. We present the first report of a nails-only phenotype in two patients with epidermolysis bullosa simplex (EBS) and a heterozygous pGlu170Lys mutation and the second reported case of EBS associated with a homozygous p.Glu170Lys mutation in the KRT5 gene. Our findings may be relevant for genetic counseling and for understanding the inheritance pattern of EBS.