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Genetic cause of epilepsy in a Greek cohort of children and young adults with heterogeneous epilepsy syndromes.

ABSTRACT: We describe a cohort of 10 unrelated Greek patients (4 females, 6 males; median age 6.5 years, range 2-18 years) with heterogeneous epilepsy syndromes with a genetic basis. In these patients, causative genetic variants, including two novel ones, were identified in 9 known epilepsy-related genes through whole exome sequencing. A patient with glycine encephalopathy was a compound heterozygote for the p.Arg222Cys and the p.Ser77Leu AMT variant. A patient affected with Lafora disease carried the homozygous p.Arg171His EPM2A variant. A de novo heterozygous variant in the GABRG2 gene (p.Pro282Thr) was found in one patient and a pathogenic variant in the GRIN2B gene (p.Gly820Val) in another patient. Infantile-onset lactic acidosis with seizures was associated with the p.Arg446Ter PDHX gene variant in one patient. In two additional epilepsy patients, the p.Ala1662Val and the novel non-sense p.Phe1330Ter SCN1A gene variants were found. Finally, in 3 patients we observed a novel heterozygous missense variant in SCN2A (p.Ala1874Thr), a heterozygous splice site variant in SLC2A1 (c.517-2A>G), as a cause of Glut1 deficiency syndrome, and a pathogenic variant in STXBP1 (p.Arg292Leu), respectively. In half of our cases (patients with variants in the GRIN2B, SCN1A, SCN2A and SLC2A1 genes), a genetic cause with potential management implications was identified.

SUBMITTER: Zaganas I

PROVIDER: S-EPMC8449081 | biostudies-literature | 2021

REPOSITORIES: biostudies-literature

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Genetic cause of epilepsy in a Greek cohort of children and young adults with heterogeneous epilepsy syndromes.

Zaganas Ioannis I Vorgia Pelagia P Spilioti Martha M Mathioudakis Lambros L Raissaki Maria M Ilia Stavroula S Giorgi Melpomeni M Skoula Irene I Chinitrakis Georgios G Michaelidou Kleita K Paraskevoulakos Evangelos E Grafakou Olga O Kariniotaki Chariklia C Psyllou Thekla T Zafeiris Spiros S Tzardi Maria M Briassoulis George G Dinopoulos Argirios A Mitsias Panayiotis P Evangeliou Athanasios A

Epilepsy & behavior reports 20210827

We describe a cohort of 10 unrelated Greek patients (4 females, 6 males; median age 6.5 years, range 2-18 years) with heterogeneous epilepsy syndromes with a genetic basis. In these patients, causative genetic variants, including two novel ones, were identified in 9 known epilepsy-related genes through whole exome sequencing. A patient with glycine encephalopathy was a compound heterozygote for the p.Arg222Cys and the p.Ser77Leu <i>AMT</i> variant. A patient affected with Lafora disease carried ...[more]

PMID: 34568804

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Genetic cause of epilepsy in a Greek cohort of children and young adults with heterogeneous epilepsy syndromes.

Publications

Genetic cause of epilepsy in a Greek cohort of children and young adults with heterogeneous epilepsy syndromes.

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