Genodermatoses with Oral Manifestations

Due to their common embryonic origin, different parts of the oral mucosa and the skin share numerous characteristics. As a result, several genetic disorders exhibit concomitant mucocutaneous lesions, affecting different subsites within the oral cavity. The oral lesions predominantly arise subsequent to cutaneous or systemic manifestations of the causative genetic condition. In rare cases, however, genodermatoses may present with antecedent involvement of the oral cavity. Orocutaneous genetic disorders generally affect multiple divisions of the oral cavity. The most common subsites include the palate, tongue, gingival and buccal mucosa. The lesions have considerably variable presentations depending on the size, color and architecture. The appearance can range from small papules and vesicles to hemorrhagic ulcerations. Some disorders can lead to severe inflammatory findings such as gingivitis and periodontitis. Conversely, oral alterations may also be very discrete and pose a diagnostic challenge. In addition, most genodermatoses manifest as multisystem disorders with a broad spectrum of symptoms including gastrointestinal, neurological, ophthalmological as well as osteological signs. The severity of systemic symptoms can vary greatly between individuals based on the penetrance and expressivity. Here, relevant genetic disorders with oral manifestations are described. Epidermolysis bullosa, dyskeratosis congenita, pachyonychia congenita, Peutz-Jeghers syndrome, Down syndrome, and Cathepsin C coding gene-related disorders are detailed in separate chapters.