TSC1 and tuberous sclerosis: The TSC1 gene on chromosome 9q34 was firstdiscovered in 1997 (van Slegtenhorst etal., 1997), though the TSC2 gene onchromosome 16p13.3 was discovered in 1993 (EuropeanChromosome 16 Tuberous Sclerosis Consortium, 1993).