A novel SYNJ1 homozygous variant causing developmental and epileptic encephalopathy in an Afro‐Caribbean individual

Autor: Mary Maj, Christie L. Taylor, Kevin Landau, Helga V. Toriello, Dong Li, Elizabeth J. Bhoj, Hakon Hakonarson, Beverly Nelson, Sarah Gluschitz, Ruth H. Walker, Andrew K. Sobering
Rok vydání: 2022
Předmět:
Zdroj: Molecular Genetics & Genomic Medicine. 11
ISSN: 2324-9269
DOI: 10.1002/mgg3.2064
Popis: SYNJ1 encodes Synaptojanin-1, a dual-function poly-phosphoinositide phosphatase that is expressed in the brain to regulate neuronal synaptic vesicle dynamics. Biallelic SYNJ1 variants cause a spectrum of clinical manifestations, from early onset parkinsonism to developmental and epileptic encephalopathy.Proband-only exome sequencing was used to identify a homozygous SYNJ1 pathogenic variant in an individual with epileptic encephalopathy. Sanger sequencing was used to confirm the variant.We present an Afro-Caribbean female who developed uncontrollable seizures shortly after birth, accompanied by developmental delay and severe generalized dystonia. She had homozygosity for a novel c.242-2A G variant in SYNJ1 with both parents being heterozygous carriers. An older sister was reported to have had a similar presentation but was not examined. Both siblings died at an approximate age of 16 years.We report a novel pathogenic variant in SYNJ1 present in homozygosity leading to developmental and epileptic encephalopathy. Currently, there are only 4 reports describing 10 individuals with SYNJ1-related developmental and epileptic encephalopathy. This case expands the clinical knowledge and the allelic heterogeneity associated with SYNJ1 variants.
Databáze: OpenAIRE