Neuropediatrics 2019; 50(05): 308-312
DOI: 10.1055/s-0039-1688410
Short Communication
Georg Thieme Verlag KG Stuttgart · New York

Infantile-Onset Paroxysmal Movement Disorder and Episodic Ataxia Associated with a TBC1D24 Mutation

Vincent Zimmern
1  Division of Pediatric Neurology, University of Texas Southwestern, Dallas, Texas, United States
Florence Riant
2  Laboratoire de Génétique Moléculaire Neurovasculaire, Groupe Hospitalier Saint-Louis-Lariboisière-Fernand-Widal, Paris, France
Emmanuel Roze
3  Sorbonne Université, Faculté de Médecine ; CNRS UMR 7225, UMR S 1127 ; Institut du Cerveau et de la Moelle épinière; APHP, Hôpital Salpêtrière, Département de Neurologie, Paris, France
Emmanuelle Ranza
4  Service of Genetic Medicine, University Hospitals, Geneva, Switzerland
Frank Lehmann-Horn
5  Department of Neurophysiology, Ulm University, Ulm, Germany
Julitta de Bellescize
6  Department of Paediatric Clinical Epileptology, Sleep Disorders and Functional Neurology, Hospices Civils de Lyon, Lyon, France
Dorothée Ville
7  Centre de référence « Déficiences Intellectuelles de causes rares », Hôpital Femme Mère Enfant, Hospices Civils de Lyon, Bron, France
Gaetan Lesca
8  Centre de référence des anomalies du développement, Service de Génétique, Hospices Civils de Lyon, Bron, France
Christian M. Korff
9  Pediatric Neurology, Child and Adolescent Department, University Hospitals, Geneva, Switzerland
› Author Affiliations
Funding This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.
Further Information

Publication History

17 December 2018

17 March 2019

Publication Date:
21 June 2019 (online)


Mutations that disrupt the TBC1D24 presynaptic protein have been implicated in various neurological disorders including epilepsy, chronic encephalopathy, DOORS (deafness, onychodystrophy, osteodystrophy, mental retardation, and seizures) syndrome, nonsyndromic hearing loss, and myoclonus. We present the case of a 22-month-old male with infantile-onset paroxysmal episodes of facial and limb myoclonus. The episodes were linked to biallelic variants in exon 2 of the TBC1D24 gene that lead to amino acid changes (c.304C >T/p.Pro102Ser and c.410T > C/p.Val137Ala), each variant being inherited from a parent. Follow-up imaging in adolescence revealed widened right cerebellar sulci. We discuss the evolving landscape of TBC1D24 associated phenotypes; this case adds to a growing body of evidence linking this gene to movement disorders in children.