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See Hansen and Møller (doi:10.1093/brain/awz318) for a scientific commentary on this article. Using polygenic risk scores from a genome-wide association study in generalized and focal epilepsy, Leu et al. reveal a significantly higher genetic burden for epilepsy in multiple cohorts of people with epilepsy compared to population controls. Quantification of common variant burden may be valuable for epilepsy prognosis and treatment., Rare genetic variants can cause epilepsy, and genetic testing has been widely adopted for severe, paediatric-onset epilepsies. The phenotypic consequences of common genetic risk burden for epilepsies and their potential future clinical applications have not yet been determined. Using polygenic risk scores (PRS) from a European-ancestry genome-wide association study in generalized and focal epilepsy, we quantified common genetic burden in patients with generalized epilepsy (GE-PRS) or focal epilepsy (FE-PRS) from two independent non-Finnish European cohorts (Epi25 Consortium, n = 5705; Cleveland Clinic Epilepsy Center, n = 620; both compared to 20 435 controls). One Finnish-ancestry population isolate (Finnish-ancestry Epi25, n = 449; compared to 1559 controls), two European-ancestry biobanks (UK Biobank, n = 383 656; Vanderbilt biorepository, n = 49 494), and one Japanese-ancestry biobank (BioBank Japan, n = 168 680) were used for additional replications. Across 8386 patients with epilepsy and 622 212 population controls, we found and replicated significantly higher GE-PRS in patients with generalized epilepsy of European-ancestry compared to patients with focal epilepsy (Epi25: P = 1.64×10−15; Cleveland: P = 2.85×10−4; Finnish-ancestry Epi25: P = 1.80×10−4) or population controls (Epi25: P = 2.35×10−70; Cleveland: P = 1.43×10−7; Finnish-ancestry Epi25: P = 3.11×10−4; UK Biobank and Vanderbilt biorepository meta-analysis: P = 7.99×10−4). FE-PRS were significantly higher in patients with focal epilepsy compared to controls in the non-Finnish, non-biobank cohorts (Epi25: P = 5.74×10−19; Cleveland: P = 1.69×10−6). European ancestry-derived PRS did not predict generalized epilepsy or focal epilepsy in Japanese-ancestry individuals. Finally, we observed a significant 4.6-fold and a 4.5-fold enrichment of patients with generalized epilepsy compared to controls in the top 0.5% highest GE-PRS of the two non-Finnish European cohorts (Epi25: P = 2.60×10−15; Cleveland: P = 1.39×10−2). We conclude that common variant risk associated with epilepsy is significantly enriched in multiple cohorts of patients with epilepsy compared to controls—in particular for generalized epilepsy. As sample sizes and PRS accuracy continue to increase with further common variant discovery, PRS could complement established clinical biomarkers and augment genetic testing for patient classification, comorbidity research, and potentially targeted treatment.

Lateral temporal lobe epilepsy (lTLE) is a rare condition characterized by auditory auras or receptive aphasia, negative MRI, and relatively benign evolution. With the low number of cases in the world, our objective was to analyze a cohort of sporadic cases with lTLE (slTLE), in order to investigate possible cerebral morphological alterations. Forty patients with lTLE (34.93 ± 12.08 years of age) and 38 healthy controls (CTRL, 34.55 ± 9.08 years of age) were enrolled from four tertiary Italian epilepsy centers, which provided brain MRI T1-weighted images following a standard protocol for patients with epilepsy. We performed group comparison by following different approaches: voxel-based morphometry (VBM, SPM8), cortical thickness (CT), and local gyrification index (lGI) (FreeSurfer 5.3). At a more conservative threshold (pÂ

Developmental and epileptic encephalopathies (DEE) encompass rare, sporadic neurodevelopmental disorders and usually with pediatric onset. As these conditions are characterized by marked clinical and genetic heterogeneity, whole-exome sequencing (WES) represents the strategy of choice for the molecular diagnosis. While its usefulness is well-established in pediatric DEE cohorts, our study is aimed at assessing the WES feasibility in adult DEE patients who experienced a diagnostic odyssey prior to the advent of this technique. We analyzed exomes from 71 unrelated adult DEE patients, consecutively recruited from an Italian cohort for the EPI25 Project. All patients underwent accurate clinical and electrophysiological characterization. An overwhelming percentage (90.1%) had already undergone negative genetic testing. Variants were classified according to the American College of Medical Genetics and Genomics guidelines. WES disclosed 24 (likely) pathogenic variants among 18 patients in epilepsy-related genes with either autosomal dominant, recessive or X-linked inheritance. Ten of these were novel. We obtained a diagnostic yield of 25.3%, higher among patients with brain malformations, early-onset epilepsy and dysmorphisms. Despite a median diagnostic delay of 38.7 years, WES analysis provided the long-awaited diagnosis for 18 adult patients, which also had an impact on the clinical management of 50% of them. This article is protected by copyright. All rights reserved.

Summary Objective To clinically and genetically characterize a large Brazilian family with autosomal dominant partial epilepsy with auditory features (ADPEAF) not related to leucine-rich, glioma-inactivated 1 (LGI1) gene. Methods Seventy family members (four married-ins) participating in the study were assessed by a detailed clinical interview and a complete neurologic examination. Genetic mapping was conducted through autosome-wide single nucleotide polymorphism (SNP) genotyping and subsequent linkage analysis on 16 and haplotype analysis on 25 subjects, respectively. Results The pedigree comprised 15 affected members, of whom 11 were included in the study (male/female: 6/5; mean age 39.5 years). All but two (III:22 and IV:92) had focal seizures with auditory aura followed by secondary generalization in 44.4%. The mean age at onset of epilepsy seizures was 13.7 years. Initial autosome-wide SNP linkage analysis conducted on 12 subjects (8 affected) pointed to a single genomic region on chromosome 19 with a maximum multipoint logarithm of the odds (LOD) score of 2.60. Further refinement of this region through SNP and microsatellite genotyping on 16 subjects (11 affected) increased the LOD score to 3.41, thereby establishing 19q13.11–q13.31 as a novel ADPEAF locus. Haplotype analysis indicated that the underlying mutation is most likely located in a 9.74 Mb interval between markers D19S416 and D19S420. Sequence analysis of the most prominent candidate genes within this critical interval (SCN1B, LGI4, KCNK6, and LRFN1) did not reveal any mutation. Significance This study disclosed a novel ADPEAF locus on chromosome 19q13.11–q13.31, contributing to future identification of a second dominant gene for this epileptic syndrome. A PowerPoint slide summarizing this article is available for download in the Supporting Information section here.

A 36-year-old right-handed man, who had experienced partial seizures since the age of 24 every time he played or listened to music with a strong emotional charge, underwent videopolygraphic recording, including autonomic variables, and brain fMRI study during which he listened to both ‘‘neutral” and ‘‘emotionally charged” music. Three right temporal seizures recorded during videopolygraphic monitoring were elicited by listening to the triggering song. The fMRI study disclosed activation in right acoustic areas during ‘‘neutral music,” whereas an ‘‘emotionally charged melody” provoked widespread activation over the right fronto-temporo-occipital area before seizure onset. The literature review disclosed 110 published cases of musicogenic epilepsy that seemed to suggest a right-sided predominance of the epileptogenic zone. Our results support the role of the right temporal lobe in musicogenic epilepsy and demonstrate that the cerebral areas activated during the period of strong emotion leading to the seizures encompass the auditory cortex activated by neutral music.

Heterozygous mutations of the leucine-rich, glioma-inactivated 1 gene (LGI1) are the major known cause of partial epilepsy with auditory features (PEAF), accounting for roughly 50% of families. Recently, a partial gene microdeletion has been reported in a single family. To assess the contribution of LGI1 microrearrangements to the pathogenesis of PEAF, we screened 50 patients negative for point mutations through multiplex ligation-dependent probe amplification (MLPA) analysis. No cryptic imbalances were found in LGI1, suggesting that LGI1 microdeletions are not a frequent cause of PEAF. Despite the small number of examined patients and the need for replication studies, these findings support the hypothesis that diagnostic screening for LGI1 microrearrangements lacks clinical utility, especially for sporadic cases, and further highlight genetic heterogeneity of familial and sporadic PEAF.

Objectives To measure the accuracy of anamnestic features collected during clinical history for the diagnosis of nocturnal frontal lobe epilepsy (NFLE). Methods A case-control diagnostic study. Participants included a case group of people with ascertained target disease (NFLE group) and a control group of people with sleep disorders potentially confounding for NFLS (NOT-NFLE group), defined by means of a consensus procedure among experts (panel diagnosis as reference standard). Two major clinical patterns defining the semeiology of the epileptic event (i.e. dystonic, DP, and/or hyperkinetic pattern, HP), and 13 additional minor features were identified, formulated as questions, and telephonically administered to NFLE and NOT-NFLE groups by a trained doctor blinded to the final diagnosis. The diagnostic accuracy of each characteristic was tested against the reference standard. Results Out of 262 selected subjects, 101 were recruited; 42 were NFLE and 59 NOT-NFLE. A positive history of DP or HP had a sensitivity of 59.5% and a specificity of 91.5%, irrespective of the other minor anamnestic features. The anamnestic model improved, with a sensitivity of 59.5% and specificity of 96.6%, if at least one of the following four minor anamnestic features was added: (a) duration less than two minutes, (b) unstructured vocalization during the episode, (c) experience of an aura preceding the motor attack, and (d) a history of tonic-clonic seizures during sleep. Conclusions The present study disclosed two major anamnestic patterns and four minor features that we called SINFLE, with unsatisfactory sensitivity but high specificity. These patterns could be the basis for developing future NFLE diagnostic criteria and to quantify the diagnostic accuracy of elements usually collected in the clinical history.