Severe Epilepsy in an Individual With a TSC2 R905Q Variant Prompting Late Diagnosis in Affected Family Members

BACKGROUND: Tuberous sclerosis complex (TSC) is a multisystemic disorder caused by inactivating variants in the mTOR pathway inhibitor genes TSC1 and TSC2. Individuals with TSC are predisposed to benign tumors in multiple organs as well as TSC-associated neuropsychiatric disorders (TAND) and epilepsy. Pathogenic variants in TSC2 are typically associated with a more severe phenotype compared with TSC1; the TSC2 R905Q variant has been shown to be …