[Inherited skin diseases - a review of selected genodermatoses]

Inherited distubances in skin structure and its function are the main cause of diseases classified as genodermatoses. The following clinical entities are classified as genodermatoses: epidermolysis bullosa, keratotic disorders, disorders of skin color, ectodermal genodermatoses, genodermatoses associated with connective tissue, vascular genodermatoses and genodermatoses with skin manifestation and elevated cancer risk. One of the most clinically heterogenous group of genodermatoses, is epidermolysis bullosa. Four main subtypes were described: simplex, dystrophic, junctional and Kindler syndrome. These diseases are caused by mutations in the genes encoding proteins forming junctions between the dermis and epidermis (eg. COL7A1, COL17A1, KRT14, KRT5 or genes coding for 332 laminin). They are inherited in an autosomal recessive or dominant manner. The disease that is inherited as a dominant, sex dependent trait, is incontinenia pigmenti (Bloch-Sulzberger syndrome) characterized by the presence of extensive pigmentation changes already in the neonatal period. In patients with incontinenia pigmenti, mutations in the NEMO gene are found. The protein encoded by NEMO is involved in the negative regulation of activity of the NFκB transcription factor that is responsible for apoptosis and cell proliferation control. In the regulation of cell proliferation, the neurofibromin (NF1) - the suppressor of RAS/MAPK signaling pathway activity, is also involved. The mutations in the NF1 gene are identified in neurofibromatosis type I - a genodermatosis with higher risk of cancer development and tumor formation. Herein, a review of selected genodermatoses in the context of their molecular pathology is presented.