Abstract
We herein report a case with a novel homozygous variant in the kyphoscoliosis peptidase (KY) gene. A 58-year-old Japanese female was referred to our hospital with a gait disturbance that gradually worsened after the age of 50. She had bilateral equinus foot deformity since early childhood. Neurological examination revealed moderate weakness of the neck, trunk, femoral, and brachial muscles, mild respiratory failure, and areflexia. Whole-exome sequencing revealed a novel homozygous frameshift variant of the KY gene, NM_178554.6:c.824del p.(Glu275Glyfs*53). Our case demonstrated that KY-associated neuromuscular disease can present with extremely slow progressive muscle weakness and respiratory failure over a long natural course.
Data availability
The data that support the findings of this study are available from the corresponding author upon reasonable request.
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Acknowledgements
We thank Initiative on Rare and Undiagnosed Disease (IRUD) for exome sequencing.
Funding
This work was supported by the Japan Agency for Medical Research and Development (AMED) under grant numbers JP23ek0109674, JP23ek0109549, JP23ek0109617, JP23ek0109648 (N. Matsumoto); JSPS KAKENHI under a grant number JP22K15901 (A. Fujita); and the Takeda Science Foundation (N. Matsumoto).
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The Human Ethics Review Committee of Kumamoto University and Yokohama City University Faculty of Medicine approved the study. Patients gave written informed consent for exome sequencing and publication.
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Misumi, Y., Yamashita, T., Kuratomi, A. et al. Long-term course of a case with a novel homozygous kyphoscoliosis peptidase variant. J Hum Genet (2024). https://doi.org/10.1038/s10038-024-01250-9
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DOI: https://doi.org/10.1038/s10038-024-01250-9
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