@article{2997420,
    title = "Delineating the motor phenotype of SGCE-myoclonus dystonia syndrome",
    author = "Vanegas, M.I. and Marcé-Grau, A. and Martí-Sánchez, L. and Mellid, S. and Baide-Mairena, H. and Correa-Vela, M. and Cazurro, A. and Rodríguez, C. and Toledo, L. and Fernández-Ramos, J.A. and Pons, R. and Aguilera-Albesa, S. and Martí, M.J. and Eiris, J. and Iglesias, G. and De Fabregues, O. and Maqueda, E. and Garriz-Luis, M. and Madruga, M. and Espinós, C. and Macaya, A. and Cabrera, J.C. and Pérez-Dueñas, B.",
    journal = "Parkinsonism and Related Disorders",
    year = "2020",
    volume = "80",
    pages = "165-174",
    publisher = "Elsevier Ireland Ltd",
    issn = "1353-8020",
    doi = "10.1016/j.parkreldis.2020.09.023",
    keywords = "adolescent;  adult;  age;  Article;  Burke Fahn Marsden rating scale;  child;  clinical article;  disease course;  disease severity;  dysgraphia;  dystonia;  female;  gait disorder;  gene;  genetic screening;  genotype;  human;  male;  motor performance;  multiplex ligation dependent probe amplification;  myoclonus dystonia;  phenotype;  priority journal;  rating scale;  Sanger sequencing;  SGCE gene;  Unified Myoclonus rating scale;  validation process;  videorecording;  walking difficulty;  writer's cramp;  child development;  dystonic disorder;  genetics;  middle aged;  motor performance;  mutation;  pathophysiology;  phenotype;  physiology;  preschool child;  severity of illness index;  young adult, sarcoglycan;  SGCE protein, human, Adolescent;  Adult;  Child;  Child Development;  Child, Preschool;  Dystonic Disorders;  Female;  Humans;  Male;  Middle Aged;  Motor Skills;  Mutation;  Phenotype;  Sarcoglycans;  Severity of Illness Index;  Young Adult",
    abstract = "Objective: To perform phenotype and genotype characterization in myoclonus-dystonia patients and to validate clinical rating tools. Method: Two movement disorders experts rated patients with the Burke-Fahn-Marsden and Unified-Myoclonus rating scales using a video-recording protocol. Clinimetric analysis was performed. SGCE mutations were screened by Sanger sequencing and multiplex ligation-dependent probe amplification. Results: 48 patients were included and 43/48 rated. Mean age at assessment was 12.9±10.5 years (range 3–51) and 88% were ≤18 years of age. Myoclonus was a universal sign with a rostro-caudal severity-gradient. Myoclonus increased in severity and spread to lower limbs during action tests. Stimulus-evoked myoclonus was observed in 86.8% cases. Dystonia was common but mild. It had a focal distribution and was action-induced, causing writer's cramp (69%) and gait dystonia (34%). The severity of both myoclonus and dystonia had a strong impact on hand writing and walking difficulties. The Unified Myoclonus Rating scale showed the best clinimetric properties for the questionnaire, action myoclonus and functional subscales, and exceeded the Burke-Fahn-Marsden scale in its utility in assessing functional impairment in MDS patients. Twenty-one different SGCE mutations were identified in 45/48 patients, eleven being novel (most prevalent p. Val187*, founder mutation in Canary Islands). Conclusion: This study quantifies the severity of the motor phenotype in SGCE-myoclonus dystonia syndrome, with a special focus on children, and identifies disabilities in gross and fine motor tasks that are essential for childhood development. Our results contribute to the knowledge of SGCE-related MDS in the early stage of evolution, where disease-modifying therapies could be initiated in order to prevent long-term social and physical burdens. © 2020 Elsevier Ltd"
}