Alonso MJ

Language: Spanish
References: 10
Page: 558-561
PDF size: 186.51 Kb.

ABSTRACT

Introduction and objectives: Tuberous sclerosis is an autosomal dominant disorder characterized by hamartomas in many organs. Two thirds of cases are sporadic and are thought to represent mutations. TSC is caused by mutations affecting either of the presumed tumor-suppresor genes, TSC1 and TSC2. Material and methods: A pair of monozygotic male twins were followed between six months and 18 years age. Twin A, with extensive brain cortical tubers, was severely mentally retarded and met criteria for autism, West, and Lennox Gastaut syndromes. The other twin B with de same extensive cortical tubers but with different locations, was not mentally retarded and did not meet criteria for autism. The twins have some similar and some notoriously different clinical features which could be explained by the Knudson hypotesis in determining phenotypic variability in TS. Genetic analysis and MRI were performed. Results: Mutation in the TSC2 was found in both. Tubers were found in twin A in both temporal lobes but were not found in twin B. Conclusions: Tuber locations in temporal lobes have a predictor of developmental outcome associated with the severity of seizures and intellectual impairments. Second hit somatic mutations are random epigenic events in which the number, size and location of tubers in identical twins could differ. Cortical tubers also show variations in their propensity to act as the focus for epileptic discharges.

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