Fig. 1

Schematic representation of the epidermis and the underlying cutaneous basement membrane zone at the dermal-epidermal junction

The skin layers affected in heritable cutaneous diseases are indicated on the left, and the specific gene products are listed on the right. Note that tissue separation in the dystrophic forms of epidermolysis bullosa (EB) occurs below the basement membrane at the level of anchoring fibrils, which consist of type VII collagen. EHK, epidermolytic hyperkeratosis; PPK, palmoplantar keratoderma.