A New Pathologic KMT2B Variant Associated with Childhood Onset Dystonia Presenting as Variable Phenotypes among Family Members

Tremor and Other Hyperkinetic Movements

article

Laura R. Owczarzak¹  Kelsey E. Hogan²  Richard T. Dineen²  Chandler E. Gill³  Mindy H. Li⁴ 

[1] Rush Medical College and Rush University Medical Center;Department of Pediatrics, Rush Medical College and Rush University Medical Center;Section of Movement Disorders, Department of Neurological Sciences, Rush University Medical Center;Division of Genetics, Department of Pediatrics, Rush Medical College and Rush University Medical Center

关键词: KMT2B;    dystonia;    DYT-28;    variable expressivity;    MLL4;    complex dystonia;   

DOI  :  10.5334/tohm.679

学科分类：社会科学、人文和艺术（综合）

来源: Ubiquity Press

【 摘 要 】

Background: KMT2B-related dystonia is a primarily childhood-onset movement disorder characterized by progressive dystonia, spasticity, and developmental delay. A minority of individuals possess an inherited KMT2B variant.Case Report: As a child, the proband experienced mild developmental delay and laryngeal dystonia which progressed to generalized dystonia. Patellar hyperreflexia, postural tremor, and everted gait were documented. Whole exome sequencing identified a heterozygous pathogenic KMT2B variant in the proband, proband’s sister, and proband’s mother who had milder presentations.Discussion: This novel KMT2B variant reflects intrafamilial variable expressivity in KMT2B-related dystonia. Further identification of variants will allow for better appreciation of the phenotypic spectrum.

【 授权许可】

CC BY