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mds21692-MDS21692.mpg13059KComparison of the clinical presentation of genetically proven Benign Hereditary Chorea (BHC) and Myoclonus-Dystonia (M-D) patients. BHC was caused by a splicing mutation of the TITF-1 gene (intron 2, 376-2A>C) in a mother and her daughter. M-D patients carried either a de novo SGCE nonsense mutation (Exon 3, R97X) or a novel missense mutation (G227V). Video assessment was based on the protocol of the WHIGET study group.Video section 1. Arms stretched.On holding the arms up straight forward only the TITF-1 mutation carriers displayed choreoathetoid movements of both hands and fingers and dystonic lateral shift of the head to the left. Patient G227V showed intermittent jerky dystonia of the left arm similar to the mother with the TITF-1 mutation. Patient R97X presented with brief, lightning-like myoclonic jerks, which are a hallmark of M-D with SGCE mutations.Video section 2. Wing beating position.Video section 3. Finger nose pointing. With both actions an intermediate worsening effect for the myoclonus of SGCE mutation carriers could be observed, whereas no worsening could be detected in TITF-1 mutation carriers.Video section 4 and 5. Drawing spirals of Archimedes I and II. While drawing spirals of Archimedes severe myoclonus in the left upper limb was apparent in both SGCE patients. Even with this most complex motor tasks, chorea in TITF-1 mutations carriers remained stable.Video section 6. Walking. Focal foot dystonia can be observed in SGCE patient G227V. Patient R97X showed dystonic posturing of the right arm during this section. With TITF-1 mutation carriers, dystonia of the legs is superimposed by choreatic movements, making their gait unsteady and ataxic.

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