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J Pediatr Genet 2023; 12(02): 159-162
DOI: 10.1055/s-0041-1723958
Case Report

Variant in CACNA1G as a Possible Genetic Modifier of Neonatal Epilepsy in an Infant with a De Novo SCN2A Mutation

Juan Jose Nieto-Barcelo
1   Hospital Universitari i Politecnic La Fe, Valencia, Spain
,
Noelia Gonzalez Montes
2   Pediatrics Unit, Hospital Universitario y Politécnico La Fe, Valencia, Spain
,
Isabel Gonzalo Alonso
2   Pediatrics Unit, Hospital Universitario y Politécnico La Fe, Valencia, Spain
,
Francisco Martinez
3   Genetics Unit, Hospital Universitario y Politécnico La Fe, Valencia, Spain
,
Maria Jose Aparisi
4   Genomics Unit, Health Research Institute Hospital La Fe (IIS La Fe), Valencia, Spain
,
Marina Martinez-Matilla
4   Genomics Unit, Health Research Institute Hospital La Fe (IIS La Fe), Valencia, Spain
,
Ana Victoria Marco Hernandez
4   Genomics Unit, Health Research Institute Hospital La Fe (IIS La Fe), Valencia, Spain
,
Miguel Tomás Vila
5   Neuropediatrics Unit, Hospital Universitario y Politécnico La Fe, Valencia, Spain
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Abstract

Mutations in SCN2A genes have been described in patients with epilepsy, finding a large phenotypic variability, from benign familial epilepsy to epileptic encephalopathy. To explain this variability, it was proposed the existence of dominant modifier alleles at one or more loci that contribute to determine the severity of the epilepsy phenotype. One example of modifier factor may be the CACNA1G gene, as proved in animal models. We present a 6-day-old male newborn with recurrent seizures in which a mutation in the SCN2A gene is observed, in addition to a variant in CACNA1G gene. Our patient suffered in the first days of life myoclonic seizures, with pathologic intercritical electroencephalogram pattern, requiring multiple drugs to achieve adequate control of them. During the next weeks, the patient progressively improved until complete remission at the second month of life, being possible to withdraw the antiepileptic treatment. We propose that the variant in CACNA1G gene could have acted as a modifier of the epilepsy syndrome produced by the mutation in SCN2A gene in our patient.

Keywords

neonatal epilepsy - SCN2A - CACNA1G - genetic modifier


Publication History

Received: 15 June 2020

Accepted: 04 January 2021

Article published online:
19 February 2021

© 2021. Thieme. All rights reserved.

Georg Thieme Verlag KG
Rüdigerstraße 14, 70469 Stuttgart, Germany

 

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