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

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