Abstract
Progressive myoclonic epilepsy is a group of neurodegenerative diseases with complex clinical and genetic heterogeneity, which is associated with spontaneous or action-induced myoclonus and progressive neurodegeneration. Since 2020, 4 families with progressive myoclonic epilepsy-11 [OMIM#618876] have been reported with a very limited spectrum of SEMA6B pathogenic variants. In our study, whole-exome sequencing was used in a proband from a nonconsanguineous Chinese family presenting with growth retardation and recurrent atonic seizures. A deletion mutation (c.1960_1978del, p.Leu654Argfs*25) in the last exon of SEMA6B was detected, which is a de novo variant and pathogenic. The new genetic evidence we reported here strengthened the gene-disease relationship, and the gene curation level between SEMA6B and progressive myoclonic epilepsy-11 became “strong” following the ClinGen SOP. Therefore, the results of this study broaden the mutation spectrum of SEMA6B in different ethnic groups and strengthen the gene-disease relationship between SEMA6B and progressive myoclonic epilepsy-11.
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Data Availability
The data and material discussed here are available in the references listed.
Abbreviations
- SEMA6B:
-
Semaphorin 6B
- MRI:
-
Magnetic resonance imaging
- EPM:
-
Progressive myoclonic epilepsy
- EEG:
-
Electroencephalogram
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Acknowledgements
We thank the patient and her family members for their cooperation and contribution.
Funding
This study was supported by grants from Jiangsu Provincial Key Research and Development Program (No. BE2018661), The Fifteenth Batch of Jiangsu Province Funds for Selection and Training of High-Level Talents (WSN-028), and Suzhou Science and Technology Development Program (SYSD2020122).
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QL and ML drafted the manuscript and contributed to conception and design of the study. DPH, PJ, and WHL cared for the patient and critically revised the article. JH and TL contributed to the data acquisition. XQC critically revised and gave final approval for publication of the paper.
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The study was based on the principles of the Declaration of Helsinki and authorized by the Institutional Review Committee of Children’s Hospital Affiliated to Soochow University. Written consent for publication was obtained from the patient.
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Li, Q., Liu, M., Huang, Dp. et al. A De Novo SEMA6B Variant in a Chinese Patient with Progressive Myoclonic Epilepsy-11 and Review of the Literature. J Mol Neurosci 71, 1944–1950 (2021). https://doi.org/10.1007/s12031-021-01880-0
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DOI: https://doi.org/10.1007/s12031-021-01880-0