Cerebellar Involvement in DYT-THAP1 Dystonia.

DYT-THAP1 dystonia is known to present a variety of clinical symptoms. To the best of our knowledge, this is the first case with DYT-THAP 1 dystonia and clinical signs of cerebellar involvement studied with transcranial magnetic stimulation in vivo. We report a case of a 51-year-old male DYT-THAP1 mutation carrier with dystonia, who additionally developed ataxia 1.5 years ago. To study cerebellar involvement in our patient, we used a TMS protocol called cerebellar inhibition (CBI). The lack of CBI in our patient strongly suggests cerebellar involvement. According to our findings, cerebellar syndrome may be part of the phenotypical spectrum of DYT-THAP1 mutations.