Dystonia-deafness syndrome 1 caused by ACTB p.(Arg183Trp) de novo variant: one novel case extending the phenotypic...

Dystonia-deafness syndrome 1 (DDS1) is a rare disorder caused by the p.(Arg183Trp) heterozygous variant in ACTB. Patients present with congenital/early-onset sensorineural deafness, then childhood/adult-onset generalized dystonia. We describe a 38 y.o patient with additional features, including brain malformations: corpus callosum and vermis hypodysplasia. These novel features expand the clinical spectrum of DDS1, and suggests an overlap with ACTB-related Baraitser-Winter syndrome. Furthermore, we report a limited improvement after Globus Pallidus internus Deep Brain Stimulation (GPi-DBS) contrary to previous publications, bringing a novel message in terms of prognosis.