%0 Journal Article
%T Expanding Phenotype of SYT1-Related Neurodevelopmental Disorder: Case Report and Literature Review.
%A Cesaroni CA
%A Spagnoli C
%A Baga M
%A Rizzi S
%A Frattini D
%A Caraffi SG
%A Pollazzon M
%A Garavelli L
%A Fusco C
%J Mol Syndromol
%V 14
%N 6
%D 2023 Dec
%M 38058756
%F 1.494
%R 10.1159/000530586
%X UNASSIGNED: Synaptotagmin 1 (SYT1), the predominant SYT isoform in the central nervous system, likely acts by promoting vesicle docking, deforming the plasma membrane via Ca2+-dependent membrane penetration.
UNASSIGNED: Here, we describe a 21-year-old woman harboring a novel variant in the SYT1 gene, who presents with a complex phenotype, featuring severe intellectual disability, absent speech, behavioral abnormalities, motor stereotypies, dystonic posturing of her hands, a hyperkinetic movement disorder in her childhood, infantile hypotonia, sialorrhea, mild dysmorphic features, epilepsy, peculiar EEG findings, and severe scoliosis.
UNASSIGNED: Based on our case and literature review on the 22 previously described patients, we can confirm a complex neurodevelopmental disorder in which, unlike other synaptopathies, epilepsy is present in a subset of cases (including our patient: 5/23, 22%), although characteristic EEG changes are far more common (10/23, 43.5%). Our patient's age allows us to provide long-term follow-up data and thus better delineate the SYT1-related clinical phenotype.