An autosomal dominant disease stemming from mutation of tuberous sclerosis complex (TSC) 1 on the 9p34 chromosome or TSC2 on16p13.3 chromosome, which are genes that encode for the hamartin and tuberin proteins, respectively, tuberous sclerosis has the classic development of hamartomas in almost every organ, and patients complain of disabling neurologic features, dermatologic features and hamartomatous lesions that are tumor-like (cortical tubers), lymphangiomyomastosis, cardiac rhabdomyoma, subependymal nodules and renal angiomyolipomas. The gene discussed is TSC2; the disease is hamartoma.