case_images: PMC11729630_01
case_images: EEG recording for Case 1. (A) Background rhythm; (B,C) interictal epileptic discharges; and (D) myoclonic seizure. EEG = electroencephalography.
case_images: medi-104-e41236-g001.jpg
case_images: PMC11729630_01_medi-104-e41236-g001.jpg
case_images: F1
case_images: Electroencephalography revealed a significantly slow background rhythm, together with generalized epileptiform discharges and myoclonic seizures (Fig. 1).
case_images: Brain MRI images of the 2 patients. Brain MRI of Patient 1 showing a slightly smaller right hippocampus on T1-weighted imaging (A) and a fluid-attenuated inversion recovery (FLAIR) sequence (B). Brain MRI of Patient 2 showing swelling of the left temporal lobe with abnormal signal intensity suggestive of FCD and an abnormal signal in the left hippocampus on T1-weighted imaging (C) and fluid-attenuated inversion recovery (FLAIR) sequence (D). FCD = focal cortical dysplasia, MRI = magnetic resonance imaging.
case_images: medi-104-e41236-g002.jpg
case_images: PMC11729630_02_medi-104-e41236-g002.jpg
case_images: F2
case_images: Brain magnetic resonance imaging revealed swelling of the left temporal lobe with abnormal signal intensity (focal cortical dysplasia, FCD), with abnormal signals observed in the left hippocampus (Fig. 2C and D).
case_images: Validation of KCNB1 variants by Sanger sequencing in patients 1 and 2 and their parents.
case_images: medi-104-e41236-g003.jpg
case_images: PMC11729630_02_medi-104-e41236-g003.jpg
case_images: F3
case_images: The de novo mutation was confirmed using Sanger sequencing (Fig. 3).
case_images: Conservation assessment of KCNB1 variant sites and KCNB1 protein tertiary structures of the wild-type and mutants. (A) In silico analysis of p.Thr387 in KCNB1 cells showing that p.Thr387 was highly conserved across different species. (B) The in silico analysis of p.Leu338 in KCNB1 revealed that p. Leu338 is highly conserved in different species. (C-F) Three-dimensional structures of wild-type and mutant KCNB1. The p.Thr387 variant altered the structure of the side strands and of the H-bonds. The p.Leu338 mutation altered the side-strand structure.
case_images: medi-104-e41236-g004.jpg
case_images: PMC11729630_02_medi-104-e41236-g004.jpg
case_images: F4
case_images: Conservation analysis revealed that the leucine at site 338 (p.Leu338) was highly conserved across multiple species (Fig. 4B). Structural modeling revealed changes in the side-strand structure at residue 338, in which leucine was substituted with phenylalanine (Fig. 4E and F).
case_images: PMC11729630_02
case_images: Brain MRI images of the 2 patients. Brain MRI of Patient 1 showing a slightly smaller right hippocampus on T1-weighted imaging (A) and a fluid-attenuated inversion recovery (FLAIR) sequence (B). Brain MRI of Patient 2 showing swelling of the left temporal lobe with abnormal signal intensity suggestive of FCD and an abnormal signal in the left hippocampus on T1-weighted imaging (C) and fluid-attenuated inversion recovery (FLAIR) sequence (D). FCD = focal cortical dysplasia, MRI = magnetic resonance imaging.
case_images: medi-104-e41236-g002.jpg
case_images: PMC11729630_02_medi-104-e41236-g002.jpg
case_images: F2
case_images: Brain magnetic resonance imaging revealed swelling of the left temporal lobe with abnormal signal intensity (focal cortical dysplasia, FCD), with abnormal signals observed in the left hippocampus (Fig. 2C and D).
case_images: Validation of KCNB1 variants by Sanger sequencing in patients 1 and 2 and their parents.
case_images: medi-104-e41236-g003.jpg
case_images: PMC11729630_02_medi-104-e41236-g003.jpg
case_images: F3
case_images: The de novo mutation was confirmed using Sanger sequencing (Fig. 3).
case_images: Conservation assessment of KCNB1 variant sites and KCNB1 protein tertiary structures of the wild-type and mutants. (A) In silico analysis of p.Thr387 in KCNB1 cells showing that p.Thr387 was highly conserved across different species. (B) The in silico analysis of p.Leu338 in KCNB1 revealed that p. Leu338 is highly conserved in different species. (C-F) Three-dimensional structures of wild-type and mutant KCNB1. The p.Thr387 variant altered the structure of the side strands and of the H-bonds. The p.Leu338 mutation altered the side-strand structure.
case_images: medi-104-e41236-g004.jpg
case_images: PMC11729630_02_medi-104-e41236-g004.jpg
case_images: F4
case_images: Conservation analysis revealed that the leucine at site 338 (p.Leu338) was highly conserved across multiple species (Fig. 4B). Structural modeling revealed changes in the side-strand structure at residue 338, in which leucine was substituted with phenylalanine (Fig. 4E and F).