Dynamic Duo: TSC1 and TSC2 Mutations in a Single Patient with Tuberous Sclerosis

Tuberous sclerosis complex (TSC) is a well recognized, highly variable, dominant genetic syndrome. The main features of the condition include dermatological manifestations, cortical brain tubers and subependymal nodules, seizures, developmental delays, and tumors of the kidneys, heart, and lungs. The two known genes associated with TSC (TSC1 and TSC2) account for 85% of identifiable mutations. There is considerable clinical overlap between the TSC1 and TSC2 phenotypes, although TSC2 mutations may cause more severe symptoms. Affected individuals are typically heterozygous for a single pathogenic mutation in TSC1 or TSC2. Here we describe the first reported case of an individual who is heterozygous for a pathogenic mutation in both TSC1 and TSC2.