Ans. is "a' i.e., Ttiberous sclerosis o Tuberous sclerosis is an autosomal dominant genetic dissorder characterized by development of variety of benign tumours in multiple organs including brain, heart, skin, eyes kidney, lung, liver.o It is caused by mutation in two seprate genes TSC l-19 and TSC 2-16o It is the most common neurocutaneous syndromes after neurofibromatosis,o Besides cutaneous manifestations childhood siezures and mental retardation are common.o It is characterized by benign tumours (hamartomas) in multiple organs including brain, heart, skin, eyes, kidney, lung, liver.o The hamartomas or the benign tumours present in tuberous sclerosis are composed of fibroblasts with collagen strands and blood vessels.The brain lesions are whitish tubers composed of fibrous tissue and glial cells.Tuberous sclerosisCutaneous invovementC.N.S. involvementOtherso Ash leaf spotso Central nervous system lesionC V.S.o Hypopigmented macules# Glioneuronal hamartomao Rhadomyoma ofo Angiofibroma (previoushy# White matter heterotopiamyocardiumcalled adenoma sebaceum)# Subependymal nodulesRenalo Shagreen patches# Subependymal giant cello Angiomyolipomao Seen on the lower trunktumourso Benign cystsBrown fibrous plaque ono Clinical featureso Renal cell carcinomathe forehead# SeizuresPulmonary manifestations # Cognitive deficitso Lymphaangiomyomatosis # Autism and behaviouralOphthalmologic problemo Retinal hamartoma o Punched out areas of chorioretinal depigmentation o Angiofibroma of eyelids o Myopia, hyperopia astigmatism