This page was created for University of Wisconsin undergraduate course Genetics 564
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About Epilepsy
Figure 1. EEG results indicating sharp peaks of activity
Our brains are made up of millions of neurons capable of firing electricity through the brain to relay messages. When there is a short circuiting of that message chain the neurons are too excited to control their impulses and all neurons begin firing at once (4). This pulse of electricity is known as a seizure and can result in staring spells, muscle jerks, or even loss of consciousness and convulsions (4).
Epilepsy is a broad term for a neurological disorder that causes these seizures to occur intermittently (5). Though seemingly rare, epileptic disorders affect about 1% of the world's population (1). Epilepsy can be a result of a family tendency or severe brain injury, but most often has no known cause (1).
In order to diagnose a patient with epilepsy, an EEG (electroencephalography) test is conducted to measure the brain's electrical activity [results pictured at right]. A machine records impulses while awake and sleeping, with sharp waves and peaks being indicative of seizure tendencies (6). By observing which parts of the brain are affected, the type of epilepsy may also be able to determined from EEG results.
Epilepsy is a broad term for a neurological disorder that causes these seizures to occur intermittently (5). Though seemingly rare, epileptic disorders affect about 1% of the world's population (1). Epilepsy can be a result of a family tendency or severe brain injury, but most often has no known cause (1).
In order to diagnose a patient with epilepsy, an EEG (electroencephalography) test is conducted to measure the brain's electrical activity [results pictured at right]. A machine records impulses while awake and sleeping, with sharp waves and peaks being indicative of seizure tendencies (6). By observing which parts of the brain are affected, the type of epilepsy may also be able to determined from EEG results.
What is Juvenile Myoclonic Epilepsy?
Figure 2. Neuronal networks within the human brain (4)
Juvenile myoclonic epilepsy accounts for 12% of all diagnosed epilepsies and it has distinct characteristics (9). The most prominent type of seizures experienced in JME are myoclonic seizures, or random rapid muscle spasms, that typically begin occurring between ages 8-20 (2). These jerks can make a person seem clumsy or uncoordinated, often causing objects to drop from their hands unexpectedly. These seizures typically occur shortly after waking. Months or years later, generalized tonic-clonic seizures (also known as grand mal seizures) causing loss of consciousness and convulsions may also begin to occur (2). These seizures occur when neuronal impulses spread to the entire brain and are often brought upon by lack of sleep, alcohol intake, or in some cases flashing lights (7).
While juvenile myoclonic epilepsy remains a chronic disease in 80% of those diagnosed, many treatment options are available to help reduce the effects of JME and keep seizures under control (7). One of the oldest forms of treatment is a ketogenic diet, high in fats and low in carbohydrates, and has been proven to lessen seizures in JME patients. More typically, patients are prescribed medications to control seizures and are safe for child use. In extreme cases of JME in which seizures cannot be controlled by medication and seizures begin in a specific location, brain resection surgeries can be conducted to remove the area of the brain which induces attacks (7).
While juvenile myoclonic epilepsy remains a chronic disease in 80% of those diagnosed, many treatment options are available to help reduce the effects of JME and keep seizures under control (7). One of the oldest forms of treatment is a ketogenic diet, high in fats and low in carbohydrates, and has been proven to lessen seizures in JME patients. More typically, patients are prescribed medications to control seizures and are safe for child use. In extreme cases of JME in which seizures cannot be controlled by medication and seizures begin in a specific location, brain resection surgeries can be conducted to remove the area of the brain which induces attacks (7).
A Genetic Link: the EFHC1 Gene
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Juvenile myoclonic epilepsy has a genetic basis. Parents with chronic JME have about a 15% of passing the syndrome to each child (3). Research has studied many families with JME prevalence and found genes associated with JME on chromosomes 6, 8, and 15 (3).
On the short arm of chromosome 6 is found the EFHC1 gene, or EF-hand domain-containing protein-1 (see red line on image 3 below). This gene is also referred to as 'myoclonin1' for its integral association with JME. Genetic studies have shown that 3-9% of all epilepsy patients worldwide have a mutation in this EFHC1 gene (9). The protein associated with this gene has a calcium binding region and is thought to be involved in calcium level regulation and cell microtubule structure (8). 
Figure 3: location of EFHC1 on chromosome 6 as indicated by red bar (8)
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Epilepsy: How to Make a Difference
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The most important way you can help those with epilepsy is knowing the proper seizure first aid, as shown in this video. When you witness a seizure, stay calm and follow these steps:
-Remove anything dangerous or sharp from the surrounding area -Put a pillow or jacket under their head to reduce head injury -Do not put anything in their mouth or hold the person down -Lay the person on their side after convulsions have stopped and remain with them until they are fully conscious Calling 911 is necessary if: -This is the person's first seizure -The person is pregnant -The person is diabetic -The seizure lasts longer than 5 minutes For more ways to help, visit the Epilepsy Foundation. 
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Website Creator: Victoria Van Vreede
Contact: [email protected]
Last Updated: 05/2014
Produced as an assignment
for undergraduate class Genetics 564
Contact: [email protected]
Last Updated: 05/2014
Produced as an assignment
for undergraduate class Genetics 564
References
(1) Epilepsy Foundation. "What is Epilepsy?". Web. 2014. http://www.epilepsy.com/101/ep101_epilepsy
(2) National Institute of Health. "Juvenile Myoclonic Epilepsy"
(3) NYU Lancone Medical Center. "Juvenile Myoclonic Epilepsy". http://epilepsy.med.nyu.edu/epilepsy/types-epilepsy/juvenile-myoclonic-epilepsy#sthash.7HrSHpeC.Q8Gw2vxK.dpbs(4) Original image by Hljod.Huskona
(4) Mount Sinai Comprehensive Pediatric Epilepsy Center. "Seizures and First Aid". Web. 2013. http://www.wehealny.org/services/bi_pedsepilepsycenter/PedsCtr.html
(5) McGoldrick, Patty. "What is Epilepsy?" Howcast. Web. http://www.youtube.com/watch?v=peDApnr2oBk&list=PL8EA6BFA2F1F036CE
(6) The Epilepsy Foundation. "EEG". https://www.epilepsy.com/epilepsy/testing_eeg(8) The Human Gene Compendium. "GeneCards" EF-Hand domain Containing 1. Web. http://www.genecards.org/cgi-bin/carddisp.pl?gene=EFHC1
(9) de Nils, L. "Juvenile myoclonic epilepsy as a possible neurodevelopmental disease: role of EFHC1 or Myoclonin1." Epilepsy Behavior Journel, 2013.
