tuberous sclerosis complex

an autosomal dominant disorder caused by mutation in either of two genes, the TSC1 gene (locus: 9q34), which encodes hamartin, or the TSC2 gene (locus: 16p13), which encodes tuberin; the two proteins are involved in tumor suppression; although hereditary, the majority of cases are due to de novo mutation. The disorder has variable manifestations, primarily neurologic and dermatologic; it is usually evident in childhood, although mild cases may not appear until later. The primary characteristics are hamartomas of the brain (tubers) that can cause seizures and mental retardation; and skin lesions such as periungual fibromas, patches of vitiligo or guttate leukoderma, shagreen patches, and cafй-au-lait spots; there may also be phakomas of the retina and hamartomas of the heart and kidney. Called also tuberous sclerosis.