1. Expanding the phenotypic spectrum of GABRG2 variants: a recurrent GABRG2 missense variant associated with a severe phenotype
- Author
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Zou, Fanggeng, McWalter, Kirsty, Schmidt, Lindsay, Decker, Amy, Picker, Jonathan D, Lincoln, Sharyn, Sweetser, David A, Briere, Lauren C, Harini, Chellamani, Network, Members of the Undiagnosed Diseases, Marsh, Eric, Medne, Livija, Wang, Raymond Y, Leydiker, Karen, Mower, Andrew, Visser, Gepke, Cuppen, Inge, van Gassen, Koen L, van der Smagt, Jasper, Yousaf, Adeel, Tennison, Michael, Shanmugham, Anita, Butler, Elizabeth, Richard, Gabriele, and McKnight, Dianalee
- Subjects
Biological Sciences ,Biomedical and Clinical Sciences ,Genetics ,Brain Disorders ,Epilepsy ,Neurodegenerative ,Neurosciences ,Aetiology ,2.1 Biological and endogenous factors ,Abnormalities ,Multiple ,Adolescent ,Child ,Female ,Humans ,Infant ,Intellectual Disability ,Male ,Motor Disorders ,Movement Disorders ,Muscle Hypotonia ,Mutation ,Missense ,Pedigree ,Phenotype ,Receptors ,GABA-A ,Severity of Illness Index ,Speech Disorders ,genetics ,seizures ,GABRG2 ,phenotype ,missense ,Members of the Undiagnosed Diseases Network ,Clinical Sciences ,Neurology & Neurosurgery - Abstract
Pathogenic missense and truncating variants in the GABRG2 gene cause a spectrum of epilepsies, from Dravet syndrome to milder simple febrile seizures. In most cases, pathogenic missense variants in the GABRG2 gene segregate with a febrile seizure phenotype. In this case series, we report a recurrent, de novo missense variant (c0.316 G > A; p.A106T) in the GABRG2 gene that was identified in five unrelated individuals. These patients were described to have a more severe phenotype than previously reported for GABRG2 missense variants. Common features include variable early-onset seizures, significant motor and speech delays, intellectual disability, hypotonia, movement disorder, dysmorphic features and vision/ocular issues. Our report further explores a recurrent pathogenic missense variant within the GABRG2 variant family and broadens the spectrum of associated phenotypes for GABRG2-associated disorders.
- Published
- 2017