Novel SYN1 Variant in Two Brothers with Focal Epilepsy and Their Prompt Response to Valproate

Abstract

Synapsins are neuron-specific phosphoproteins that modulate neurotransmitter release, synaptic plasticity, and molecular processes shaping higher brain functions. Pathogenic synapsin-1 (SYN1) variants are associated with epilepsy, intellectual disabilities, and behavioral problems. We detected a novel SYN1 variant [c.477_479delTGG (p.Gly160del)] in brothers with focal epilepsy with secondary generalization. The deleted amino acid was found to be highly conserved among mammalian species. In electroencephalography, the older brother showed a bioelectrical status epilepticus and was also diagnosed with attention deficit hyperactivity disorder. Behavioral abnormalities were seen before or after the seizures. Both patients responded quickly to treatment with valproate. Our case reports are consistent with the clinical heterogeneity of the pathogenic SYN1 variants described in the literature.

Keywords

SYN1 - valproate - epilepsy - variant - children

Publication History

Received: 05 March 2022

Accepted: 17 January 2023

Accepted Manuscript online:
24 January 2023

Article published online:
15 March 2023

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