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A Novel De Novo Variant in DYNC1H1 Causes Spinal Muscular Atrophy Lower Extremity Predominant in Identical Twins: A Case Report.

ABSTRACT: Mutations in DYNC1H1 have been shown to cause spinal muscular atrophy lower extremity predominant type 1 (SMALED1), an autosomal dominant genetic neuromuscular disorder characterized by degeneration of spinal cord motor neurons resulting in muscle weakness. Here, we describe monozygotic twins, one with a more severe upper motor neuron phenotype as a result of a suspected perinatal hypoxic-ischemic event and the other presenting a typical lower motor neuron phenotype. Using exome sequencing, we identified the novel de novo variant c.752G>T; p.Arg251Leu in DYNC1H1. We thereby add this variant to the growing list of mutations in DYNC1H1 that cause SMALED1.

SUBMITTER: Derksen A

PROVIDER: S-EPMC8312150 | biostudies-literature | 2021 Jan-Dec

REPOSITORIES: biostudies-literature

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A Novel De Novo Variant in DYNC1H1 Causes Spinal Muscular Atrophy Lower Extremity Predominant in Identical Twins: A Case Report.

Derksen Alexa A Mirchi Amytice A Tran Luan T LT Cao-Lei Lei L Oskoui Maryam M Srour Myriam M Poulin Chantal C Bernard Geneviève G

Child neurology open 20210101

Mutations in DYNC1H1 have been shown to cause spinal muscular atrophy lower extremity predominant type 1 (SMALED1), an autosomal dominant genetic neuromuscular disorder characterized by degeneration of spinal cord motor neurons resulting in muscle weakness. Here, we describe monozygotic twins, one with a more severe upper motor neuron phenotype as a result of a suspected perinatal hypoxic-ischemic event and the other presenting a typical lower motor neuron phenotype. Using exome sequencin ...[more]

PMID: 34368388

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Exome Sequencing Identifies DYNC1H1 Variant Associated With Vertebral Abnormality and Spinal Muscular Atrophy With Lower Extremity Predominance.

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