Copy number variation in genetic epilepsy with febrile seizures plus

Genome-wide identification and phenotypic characterization of seizure-associated copy number variations in 741,075 individuals

Copy number variants (CNV) are established risk factors for neurodevelopmental disorders with seizures or epilepsy. With the hypothesis that seizure disorders share genetic risk factors, we pooled CNV data from 10,590 individuals with seizure disorders, 16,109 individuals with clinically validated epilepsy, and 492,324 population controls and identified 25 genome-wide significant loci, 22 of which are novel for seizure disorders, such as deletions at 1p36.33, 1q44, 2p21-p16.3, 3q29, 8p23.3-p23.2, 9p24.3, 10q26.3, 15q11.2, 15q12-q13.1, 16p12.2, 17q21.31, duplications at 2q13, 9q34.3, 16p13.3, 17q12, 19p13.3, 20q13.33, and reciprocal CNVs at 16p11.2, and 22q11.21. Using genetic data from additional 248,751 individuals with 23 neuropsychiatric phenotypes, we explored the pleiotropy of these 25 loci. Finally, in a subset of individuals with epilepsy and detailed clinical data available, we performed phenome-wide association analyses between individual CNVs and clinical annotations categorized through the Human Phenotype Ontology (HPO). For six CNVs, we identified 19 significant associations with specific HPO terms and generated, for all CNVs, phenotype signatures across 17 clinical categories relevant for epileptologists. This is the most comprehensive investigation of CNVs in epilepsy and related seizure disorders, with potential implications for clinical practice.

Microdeletions and microduplications linked to severe congenital disorders in infertile men

Data on the clinical validity of DNA copy number variants (CNVs) in spermatogenic failure (SPGF) is limited. This study analyzed the genome-wide CNV profile in 215 men with idiopathic SPGF and 62 normozoospermic fertile men, recruited at the Andrology Clinic, Tartu University Hospital, Estonia. A two-fold higher representation of > 1 Mb CNVs was observed in men with SPGF (13%, n = 28) compared to controls (6.5%, n = 4). Seven patients with SPGF were identified as carriers of microdeletions (1q21.1; 2.4 Mb) or microduplications (3p26.3, 1.1 Mb; 7p22.3-p22.2, 1.56 Mb; 10q11.22, 1.42 Mb, three cases; Xp22.33; 2.3 Mb) linked to severe congenital conditions. Large autosomal CNV carriers had oligozoospermia, reduced or low-normal bitesticular volume (22-28 ml). The 7p22.3-p22.2 microduplication carrier presented mild intellectual disability, neuropsychiatric problems, and short stature. The Xp22.33 duplication at the PAR1/non-PAR boundary, previously linked to uterine agenesis, was detected in a patient with non-obstructive azoospermia. A novel recurrent intragenic deletion in testis-specific LRRC69 was significantly overrepresented in patients with SPGF compared to the general population (3.3% vs. 0.85%; χ² test, OR = 3.9 [95% CI 1.8-8.4], P = 0.0001). Assessment of clinically valid CNVs in patients with SPGF will improve their management and counselling for general and reproductive health, including risk of miscarriage and congenital disorders in future offspring.

Mechanism of the promotion of GEFS+ by the STAT3-mediated expression of interleukin-6

BACKGROUND

Genetic epilepsy with febrile seizures plus (GEFS+) is generally considered an ion channelopathy. To date, there have been few studies on inflammation associated with various types of epilepsy, and it remains unclear whether the inflammatory mechanism plays a key role in epilepsy.

METHODS

In order to explore the role of the regulatory mechanism of immune factor expression in the pathogenesis of GEFS+, the present study detected the expression level of relevant immune factors such as interleukin-6 (IL-6) in peripheral blood of GEFS+ mice.

RESULTS

The cluster of differentiation 4⁺/cluster of differentiation 8⁺ (CD4⁺/CD8⁺) ratio in the GEFS+ mice was decreased, while the signal transducer and activator of transcription 3 (STAT3) was also activated and the IL-6 was upregulated. Inhibit of STAT3 can lead to the GEFS+ asymptomatically due to the downregulated IL-6, IL-1β, and complement factor H (CFH) levels. Suppression of STAT3 can also inhibited the epileptic seizures, the CD8⁺ T cells were declined after the IL-6 was neutralized.

CONCLUSIONS

The purpose of this study was to analyze and compare the effect of STAT3 expression and activation differences on GEFS+ attack, and to clarify the relationship between various cytokines and GEFS+ outbreak. Inhibiting the expression of pro-inflammatory factors can further prevent GEFS+ attack, which supports that IL-6 is one of the important factors that aggravate the clinical symptoms of GEFS+. We expected to provide a theoretical basis for immunosuppressive therapy of GEFS+ and a new way for its clinical treatment.

Auditory phoneme discrimination, articulation, and language disorders in patients with genetic epilepsy with febrile seizures plus: A case-control study

INTRODUCTION

Genetic epilepsy with febrile seizures plus (GEFS+) is an epilepsy syndrome with clinical heterogeneity that was first described in 1997. Central auditory processing (CAP) is defined as the neurophysiological process in decoding sound waves from the outer ear to the auditory cortex. The present study aimed to analyze CAP and phonological disorders in preschool-age children with GEFS+.

MATERIAL AND METHOD

This is a prospective case-control study. Twenty-seven patients diagnosed with GEFS+ aged between 4 years and 6 years and 6 months and 31 healthy controls in the same age range were included in the study. Phonological sensitivity test (SAT) and auditory discrimination test (İAT) were applied to both groups, and the results of both groups were statistically compared.

RESULTS

The SAT and İAT raw and Z scores of the subjects in the study group were found to be significantly higher than those of the control group (p = 0.001; p < 0.01). Electroencephalography (EEG) status of the patients or the duration of antiseizure medication use did not have a statistically significant effect on the outcome.

CONCLUSION

Patients with GEFS+ have a significantly high impairment in both articulation and auditory discrimination of phonemes compared with the healthy population. Early diagnosis and early treatment of this condition can prevent potential literacy problems and the development of dyslexia in the future.

Genetic Testing in Pediatric Epilepsy

With the advent of next generation sequencing technology there has been a spurt of papers on genetics in epilepsy in children. Genetic testing has now become an essential part of clinical practice in epilepsy. It helps in reaching an etiological diagnosis, providing prognostic information, guiding therapy precisely indicated for the patient and avoiding drugs that may worsen the seizures. Once the pathogenic variant has been found, this enables determining and counseling the risk of recurrence to the patient and other relatives at risk. It also makes available different reproductive options such as prenatal diagnosis or pre-implantation diagnosis. The authors describe the benefits, the clinical situations that require genetic testing, the types of genetic tests that are available, and how to choose the appropriate test and their likely yields. Genetic counseling, both pre- and post-test that should be provided is described briefly. Two useful tables are included that depict the therapy for variants in different epilepsy genes.