Hyperekplexia in Patients With CTNNB1 Mutation

A few years ago, a new genetic disorder (OMIM # 615075) has been associated with loss-of-function variations in the CTNNB1 gene. The clinical features include a delayed psychomotor development usually leading to severe intellectual disability with or without autistic spectrum disorders, progressive spastic diplegia, and various visual defects. Among over 30 cases described worldwide, 2 were reported with an exaggerated startle response to sudden stimulus corresponding to a very rare neurological phenomenon called hyperekplexia. The investigators also have a 3rd patient carrying a CTNNB1 syndrome associated with hyperekplexia.