Evaluation of the etiology of epilepsy and/or developmental delay in children with next generation sequencing: A single center experience

Objectives: In this study we aimed to understand the genetic etiology in children presenting with epilepsy and/or developmental delay(DD) by using next generation sequencing (NGS). Methods: We included children with the diagnosis of epilepsy and/or developmental delay between January 2019 and December 2021.The patients were evaluated with the next generation sequencing (whole exome sequencing-WES or whole genome sequencing-WGS or both) in our genetic laboratory. Sociodemographic, clinical, EEG and MRI findings were retrospectively examined and the results of the genetic tests were evaluated according to the recent genetics literature. Results: A total of 87 patients were included.51 patients (58.62%) were male and 36 (41.37%) were female.The mean age of patients was 4,08 years.9 patients (10,34%) had only epilepsy, 52 patients (59.77%) had both DD and epilepsy, 26 patients had only DD.27 (35,06%) out of 77 patients who had WES had pathogenic or likely pathogenic variant, 16 (20.77%) had variant of unknown significance (VUS).Five out of 10 patients (50%) who had WGS had pathogenic or likely pathogenic varians and 4 had (40%) VUS.Five patients who had negative WES (5.74%) had a diagnosis with chromosomal microarray.In total, 57 out of 87 patients (65.51%) had a genetic variant associated with their disease.13 patients (14,94%) had a diagnosis with a known specific treatment. Conclusion: NGS helps to diagnose children with epilepsy and/or DD precisely and also provides a correct prognosis, specific treatment methods and multidisiplinary approach.
Keywords: Epilepsy, developmental delay, next generation sequencing, children