RT Book, Section A1 Poduri, Annapurna A1 Harini, Chellamani A2 Murray, Michael F. A2 Babyatsky, Mark W. A2 Giovanni, Monica A. A2 Alkuraya, Fowzan S. A2 Stewart, Douglas R. SR Print(0) ID 1102704797 T1 Epilepsy T2 Clinical Genomics: Practical Applications in Adult Patient Care YR 2014 FD 2014 PB McGraw-Hill Education PP New York, NY SN 9780071622448 LK accessbiomedicalscience.mhmedical.com/content.aspx?aid=1102704797 RD 2024/03/29 AB Disease summary:Epilepsy is a common condition affecting 0.5% to 1% of the world’s population in which genetics play an important role. Genetic factors play a predominant role in about 40% of all epilepsies. Common epilepsies are believed to have complex genetic inheritance, influenced by variation in several susceptibility genes with or without an acquired or environmental component. Idiopathic generalized epilepsy (more recently called genetic generalized epilepsy [GGE]) represents 20% to 30% of all epilepsies, and the designation of genetics is based on evidence from family history patterns, twin studies, and known monogenic epilepsies, though the latter represent only a small minority of the epilepsies.Differential diagnosis:Syncope, nonepileptic seizures, migraine, movement disorders, metabolic disturbances, and sleep disordersMonogenic forms:Mutated genes may encode components of neuronal voltage-gated ion channels (sodium and potassium channels) or ligand-gated ion channels (acetylcholine and g-aminobutyric acid type A [GABA-A] receptors) or nonion channel genes LGI1 (leucine-rich glioma-inactivated 1).Family history:There is 8% to 12% risk for developing epilepsy among first-degree relatives of individuals when compared to the risk of approximately 0.5% in the general population. Both generalized and focal epilepsy can be caused by genetic mutations.Twin studies:There is a high concordance of epilepsy for monozygous twins compared to dizygotic twins for generalized epilepsies (~0.8), evidence for the influence of genetic factors in epilepsy especially GGE.Environmental factors:The role of environmental factors and other epigenetic factors in epilepsy is suspected but not well characterized, although fever can be a precipitating factor in some epilepsy syndromes.Genome-wide associations:GWAS failed to identify common genetic variants that contribute to the risk of focal epilepsy.Pharmacogenomics:None known.