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Congenital myopathy-1B caused by a homozygous RYR1 variant: A case report
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1
Department of Pediatric Genetics, Faculty of Medicine, Necmettin Erbakan University, Konya,
Turkey
2
Department of Pediatric Neurology, Faculty of Medicine, Necmettin Erbakan University, Konya,
Turkey
GPD, 4748 https://doi.org/10.36922/gpd.4748
Submitted: 3 September 2024 | Accepted: 12 November 2024 | Published: 27 December 2024
© 2024 by the Author(s). This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution 4.0 International License ( https://creativecommons.org/licenses/by/4.0/ )
Abstract
Congenital myopathies are a group of clinically and genetically diverse neuromuscular diseases that often present with stable and/or slowly progressive trunk and proximal weakness. Genetic analysis can help diagnose each congenital myopathy more accurately. Although an increasing number of other causative genes have been reported, ryanodine receptor 1 (RYR1)-related myopathy is the most common cause. Herein, we report the clinical presentation of a patient with congenital myopathy-1B (multiminicore disease) that was caused by a c.115 G>A homozygous variant of RYR1. The patient had normal cognitive abilities but was developmentally delayed and unable to walk. Electromyography revealed myogenic changes. The c.115G>A variant located in the second exon of RYR1 was found to be homozygous in the congenital neuromuscular gene panel. The patient’s parents and sister both carried the heterozygous variant. Clinical differences between family members with the homozygous and heterozygous variants of RYR1 highlight the correlation between the genotype and phenotype.
Keywords
Congenital myopathy-1B
Ryanodine receptor 1-related variants
Multiminicore disease
Funding
None.
Conflict of interest
The authors declare that they have no competing interests.
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