Genome-wide Polygenic Burden of Rare Deleterious Variants in Sudden Unexpected Death in Epilepsy.

Sudden unexpected death in epilepsy (SUDEP) represents the most severe degree of the spectrum of epilepsy severity and is the commonest cause of epilepsy-related premature mortality. The precise pathophysiology and the genetic architecture of SUDEP remain elusive. Aiming to elucidate the genetic basis of SUDEP, we analysed rare, protein-changing variants from whole-exome sequences of 18 people who died of SUDEP, 87 living people with epilepsy and 1479 non-epilepsy disease controls.

Homozygous mutations in the SCN1A gene associated with genetic epilepsy with febrile seizures plus and Dravet syndrome in 2 families.

Background: Mutations in the gene encoding the alpha subunit of the voltage-gated sodium channel SCN1A are associated with several epilepsy syndromes. These range from severe phenotypes including Dravet syndrome to milder phenotypes such as genetic epilepsy with febrile seizures plus (GEFS+). To date the sequence variants identified have been heterozygous in nature as one would expect for a disorder that occurs de novo or is dominantly inherited.

Genotype phenotype associations across the voltage-gated sodium channel family.

Mutations in genes encoding voltage-gated sodium channels have emerged as the most clinically relevant genes associated with epilepsy, cardiac conduction defects, skeletal muscle channelopathies and peripheral pain disorders. Geneticists in partnership with neurologists and cardiologists are often asked to comment on the clinical significance of specific mutations. We have reviewed the evidence relating to genotype phenotype associations among the best known voltage-gated sodium channel related disorders.

SCN1A Genetic Test for Dravet Syndrome (Severe Myoclonic Epilepsy of Infancy and its Clinical Subtypes) for use in the Diagnosis, Prognosis, Treatment and Management of Dravet Syndrome.

Unlabelled: Classic Dravet syndrome is also termed severe myoclonic epilepsy of infancy (SMEI). There are subtle phenotypic variants of Dravet which may have all the features of the syndrome except one, such as without myoclonic seizures, onset in the second year or without generalized spike and wave on EEG. These have been termed borderline variants of SMEI.

The clinical utility of an SCN1A genetic diagnosis in infantile-onset epilepsy.

Aim: Genetic testing in the epilepsies is becoming an increasingly accessible clinical tool. Mutations in the sodium channel alpha 1 subunit (SCN1A) gene are most notably associated with Dravet syndrome. This is the first study to assess the impact of SCN1A testing on patient management from both carer and physician perspectives.

Dravet syndrome as epileptic encephalopathy: evidence from long-term course and neuropathology.

Dravet syndrome is an epilepsy syndrome of infantile onset, frequently caused by SCN1A mutations or deletions. Its prevalence, long-term evolution in adults and neuropathology are not well known. We identified a series of 22 adult patients, including three adult post-mortem cases with Dravet syndrome.