An overview of the most commonly encountered inherited skin diseases is presented here. A few rarer disorders are also reviewed because of particular clinical importance in their pathogenesis or treatment. Internet resources that include information about these disorders include GeneClinics (www.genetests.org) and Mendelian Inheritance in Man (OMIM) (http://omim.org/).
The genodermatoses are a large group of inherited single-gene disorders with skin manifestations. Many of these disorders are rare. However, the recognition of their skin findings is important not only for the initiation of appropriate dermatologic therapy, but also for the detection of other associated abnormalities in these frequently multisystem disorders, including malignancy [1-3].
DISORDERS WITH MALIGNANT POTENTIAL
This group of genodermatoses is of particular importance because of the association of skin findings with the development of malignancies, both cutaneous and noncutaneous (table 1). Examples include basal cell nevus syndrome, Gardner syndrome, Peutz-Jeghers syndrome, and Xeroderma pigmentosum.
Basal cell nevus syndrome — The basal cell nevus syndrome (nevoid basal cell carcinoma syndrome, Gorlin syndrome, MIM #109400) is a rare disorder of autosomal dominant inheritance that results from germline mutations of the human patched gene (PTCH). (See "Nevoid basal cell carcinoma syndrome".)
Affected patients have both developmental anomalies and postnatal tumors, especially multiple basal cell carcinomas (BCCs), usually by age 35. Most have the following clinical features: