Phenotypic characterization of individuals with SYNGAP1 pathogenic variants reveals a potential correlation between posterior dominant rhythm and developmental progression
Posted on 2019-08-09 - 04:07
Abstract Background The SYNGAP1 gene encodes for a small GTPase-regulating protein critical to dendritic spine maturation and synaptic plasticity. Mutations have recently been identified to cause a breadth of neurodevelopmental disorders including autism, intellectual disability, and epilepsy. The purpose of this work is to define the phenotypic spectrum of SYNGAP1 gene mutations and identify potential biomarkers of clinical severity and developmental progression. Methods A retrospective clinical data analysis of individuals with SYNGAP1 mutations was conducted. Data included genetic diagnosis, clinical history and examinations, neurophysiologic data, neuroimaging, and serial neurodevelopmental/behavioral assessments. All patients were seen longitudinally within a 6-year period; data analysis was completed on June 30, 2018. Records for all individuals diagnosed with deleterious SYNGAP1 variants (by clinical sequencing or exome sequencing panels) were reviewed. Results Fifteen individuals (53% male) with seventeen unique SYNGAP1 mutations are reported. Mean age at genetic diagnosis was 65.9âmonths (28â174âmonths). All individuals had epilepsy, with atypical absence seizures being the most common semiology (60%). EEG abnormalities included intermittent rhythmic delta activity (60%), slow or absent posterior dominant rhythm (87%), and epileptiform activity (93%), with generalized discharges being more common than focal. Neuroimaging revealed nonspecific abnormalities (53%). Neurodevelopmental evaluation revealed impairment in all individuals, with gross motor function being the least affected. Autism spectrum disorder was diagnosed in 73% and aggression in 60% of cases. Analysis of biomarkers revealed a trend toward a moderate positive correlation between visual-perceptual/fine motor/adaptive skills and language development, with posterior dominant rhythm on electroencephalogram (EEG), independent of age. No other neurophysiology-development associations or correlations were identified. Conclusions A broad spectrum of neurologic and neurodevelopmental features are found with pathogenic variants of SYNGAP1. An abnormal posterior dominant rhythm on EEG correlated with abnormal developmental progression, providing a possible prognostic biomarker.
CITE THIS COLLECTION
DataCiteDataCite
3 Biotech3 Biotech
3D Printing in Medicine3D Printing in Medicine
3D Research3D Research
3D-Printed Materials and Systems3D-Printed Materials and Systems
4OR4OR
AAPG BulletinAAPG Bulletin
AAPS OpenAAPS Open
AAPS PharmSciTechAAPS PharmSciTech
Abhandlungen aus dem Mathematischen Seminar der Universität HamburgAbhandlungen aus dem Mathematischen Seminar der Universität Hamburg
ABI Technik (German)ABI Technik (German)
Academic MedicineAcademic Medicine
Academic PediatricsAcademic Pediatrics
Academic PsychiatryAcademic Psychiatry
Academic QuestionsAcademic Questions
Academy of Management DiscoveriesAcademy of Management Discoveries
Academy of Management JournalAcademy of Management Journal
Academy of Management Learning and EducationAcademy of Management Learning and Education
Academy of Management PerspectivesAcademy of Management Perspectives
Academy of Management ProceedingsAcademy of Management Proceedings
Academy of Management ReviewAcademy of Management Review
Jimenez-Gomez, Andres; Niu, Sizhe; Andujar-Perez, Fabiola; McQuade, Elizabeth; Balasa, Alfred; Huss, David; et al. (2019). Phenotypic characterization of individuals with SYNGAP1 pathogenic variants reveals a potential correlation between posterior dominant rhythm and developmental progression. figshare. Collection. https://doi.org/10.6084/m9.figshare.c.4612877.v1