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

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.

Keywords

DNM1L - DLP1 - mitochondrial - sensory neuronopathy - spasticity - dystonia - ataxia

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.

Publication History

Received: 15 May 2023

Accepted: 14 June 2023

Article published online:
28 July 2023

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