Journal of Pediatric Neurology 2023; 21(06): 475-478
DOI: 10.1055/s-0043-1771352
Case Report

DNM1L Variant Presenting as Adolescent-Onset Sensory Neuronopathy, Spasticity, Dystonia, and Ataxia

1   Department of Neurology, University Hospitals Cleveland Medical Center, Cleveland, Ohio, United States
2   Department of Neurology, Case Western Reserve University, Cleveland, Ohio, United States
,
Gabrielle Lemire
3   Center for Mendelian Genomics and Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States
4   Division of Genetics and Genomics, Boston Children's Hospital, Boston, Massachusetts, United States
,
Grace E. VanNoy
3   Center for Mendelian Genomics and Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States
,
Christina Austin-Tse
3   Center for Mendelian Genomics and Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States
,
Anne O'Donnell-Luria
3   Center for Mendelian Genomics and Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States
4   Division of Genetics and Genomics, Boston Children's Hospital, Boston, Massachusetts, United States
,
Camilla Kilbane
1   Department of Neurology, University Hospitals Cleveland Medical Center, Cleveland, Ohio, United States
2   Department of Neurology, Case Western Reserve University, Cleveland, Ohio, United States
› Author Affiliations
Funding Genome sequencing and analysis of this individual was funded by the NHGRI, NHLBI, and National Eye Institute (NEI) grant UM1 HG008900, NHGRI grant R01 HG009141, and by the Chan Zuckerberg Initiative to the Rare Genomes Project.

Abstract

DMN1L encodes for dynaminlike protein 1 (DLP1), which plays a key role in peroxisomal and mitochondrial fission. Individuals with heterozygous variants in DNM1L present with a wide range of neurologic symptoms, including encephalopathy, epilepsy, and motor deficits. Here we report on a woman presenting with adolescence onset of sensory neuronopathy, spasticity, dystonia, and ataxia. Trio genome sequencing identified a heterozygous variant in DNM1L (NM_012062.3 c.121G > A/p.Val41Met), which was thought to be pathogenic. This case describes the latest known symptomatic onset of DMN1L-related disease described in the literature. We highlight our approach to a challenging diagnostic workup and interpretation of a specific variant that has not been previously reported. Furthermore, the case highlights the diagnostic importance of utilizing genomic sequencing and research studies for patients with rare disease.

Author Contributions

A.W. was involved in writing the original draft and editing. G.L., G.V., C.A., and A.L. contributed to the methodology and writing, reviewing, and editing the manuscript. C.K. contributed to conceptualization and writing, reviewing, and editing the manuscript.


Data Availability

The data that support the findings are available on request from the corresponding author.


Supplementary Material



Publication History

Received: 15 May 2023

Accepted: 14 June 2023

Article published online:
28 July 2023

© 2023. Thieme. All rights reserved.

Georg Thieme Verlag KG
Rüdigerstraße 14, 70469 Stuttgart, Germany

 
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