Fragile X syndrome is caused by a gene mutation on the X chromosome. If a father has fragile X syndrome, he will pass a milder form of the disorder to his daughters but will not pass it to his sons.
The gene is often passed down in a milder form, so that families may be unaware that they carry it. Rett syndrome is caused, in most cases, by a newly discovered mutation on the X chromosome.
In a few families, the syndrome is inherited in an X-linked dominant pattern. It was initially believed that Rett syndrome affects only girls; however, it has recently been found to occur rarely in boys as well.
The disorder usually develops between one and two years of age. Acute intermittent porphyria is a rare disease caused by a gene mutation in the HMBS gene on chromosome 11, which controls a step in the production of hemoglobin. The symptoms of the condition consist of severe attacks of abdominal pain, vomiting, digestive problems, and seizures. The attacks are triggered by factors such as certain drugs, smoking, dieting, other illnesses and stress.
Leukodystrophies are disorders affecting the production or maintenance of the fatty covering of nerves. As a result, signals travel more slowly than normal through the nervous system. This disrupts the functioning of the nervous system, which can sometimes include seizures. Leukodystrophies can be caused by mutations in many different genes; their inheritance pattern depends on which gene is affected.
In some cases, the mutation arises spontaneously. More than 30 leukodystrophies have been identified. Some specific leukodystrophies are Alexander disease, Canavan disease and Krabbe disease. Mucopolysaccharidoses are disorders of the enzymes that break down molecules called glycosaminoglycans into smaller components, which are needed to build connective tissue. Over time, the glycosaminoglycans build up in the body and cause permanent damage to cells, bone, skeletal structure, and organs.
There are many different mucopolysaccharidoses, caused by many different gene mutations. Sanfilippo syndrome, one of the mucopolysaccharidoses, frequently causes seizures. A number of epilepsy syndromes are thought to be multifactorial or complex disorders, in which genetic and environmental factors both seem to play a part.
Myoclonic-astatic epilepsy usually appears between two and five years of age, with a variety of seizure types. The relatives of affected children often have other forms of epilepsy or febrile seizures, suggesting a strong genetic component. It is possible that several different genes are involved, as well as other modifying factors. Benign epilepsy of childhood with centrotemporal spikes BECTS , also known as benign rolandic epilepsy, is one of the most common childhood epilepsy syndromes.
It usually begins between ages five and 10 years and disappears in adolescence. Benign myoclonic epilepsy of infancy is a rare condition that usually affects children between six months and three years old.
Children with the syndrome have brief myoclonic seizures that are usually easy to control with medication. Juvenile myoclonic epilepsy usually appears in adolescents between 12 and 18 years old. People with this syndrome have myoclonic jerks, usually in the shoulders and arms, upon awakening or shortly afterward. Half of patients with this condition have relatives with epilepsy. The genetic basis of this syndrome is complex and the mechanism of transmission is unclear.
It is possible that several different genes are responsible. Childhood absence epilepsy begins between four and 10 years old, and involves severe and frequent absence seizures. Some researchers have found links to chromosome 1 or chromosome 8. However, it seems likely that other factors besides genetics are involved.
Juvenile absence epilepsy is similar to childhood absence epilepsy, but usually begins later in life, between 10 and 17 years old. Some children with this syndrome have family members with epilepsy. Mitochondrial disorders occur when the mitochondria fail and are not able to produce the energy a cell or tissue needs. These disorders appear to cause most damage to the brain, heart, liver, skeletal muscles, and kidney, which are tissues with the highest demands for energy.
Mitochondrial disorders most often present as muscle weakness with neurological problems; other symptoms include poor growth, heart failure due to cardiomyopathy, gastrointestinal disorders, liver disease, and diabetes.
People with this syndrome manifest it in a wide variety of ways; some are unaffected, some develop epilepsy later in life, and others develop severe, progressive epilepsy with dementia as children. The mutation is passed from mother to child.
Chromosomal mutations, damage or faulty duplication are at the root of conditions like Down syndrome, Wolf-Hirschhorn syndrome, Angelman syndrome, and ring chromosome abnormalities.
Down syndrome is caused by an additional copy of chromosome This means that instead of the normal pair of chromosomes, there are 3 copies. This is called a trisomy. Down syndrome is also referred to as Trisomy A trisomy is caused by an error that occurs during cell division.
Wolf-Hirschhorn syndrome occurs when part of chromosome 4 is deleted. Ring chromosome abnormalities are rare disorders that occur when both ends of a chromosome are damaged and the chromosome reforms in a ring shape. Many genes have an effect on brain development. Changes in even one of these genes can affect how the brain functions.
Mutations in certain genes have been identified as causes of brain malformations, which can lead to epilepsy. Both of these malformations can lead to seizures. Many other genes are associated with specific ion channels. Skip to main content. Is Epilepsy Inherited? For instance, not everyone who has a serious head injury a clear cause of seizures will get epilepsy.
Those who do develop epilepsy may be more likely to have a history of seizures in their family. This family history suggests that it is easier for them to develop epilepsy than for people with no genetic tendency. When seizures begin from both sides of the brain at the same time it's called generalized epilepsy. Generalized epilepsy is more likely to be inherited and involve genetic factors than partial or focal epilepsy. In recent years, genetic links to some forms of partial epilepsy have been found.
Are the brothers and sisters of children with epilepsy more likely to develop it? Their risk is slightly higher than usual, because there may be a genetic tendency in the family for seizures and epilepsy. Even so, most brothers and sisters will not develop epilepsy. If your child is in the hospital with seizures, medicine may be given by injection or intravenously by vein IV.
It is important to give your child medicine on time and as prescribed. The dose may need to be adjusted for the best seizure control. All medicines can have side effects. If your child has side effects, talk to the healthcare provider. Do not stop giving medicine to your child. This can cause more or worse seizures. While your child is taking medicine, he or she may need tests to see how well the medicine is working.
Your child may have:. Blood tests. Your child may need blood tests often to check the level of medicine in his or her body. Based on this level, the healthcare provider may change the dose of medicine. Your child may also have blood tests to check the effects of the medicine on his or her other organs. An EEG is a procedure that records the brain's electrical activity. This is done by attaching electrodes to the scalp. Your child may not need medicine for life.
Some children are taken off medicine if they have had no seizures for 1 to 2 years. This will be determined by your child's healthcare provider. Your child may be treated with any of the below:. A ketogenic diet. This type of diet is very high in fat, and very low in carbohydrates.
Enough protein is included to help promote growth. The diet causes the body to make ketones. These are chemicals made from the breakdown of body fat. The brain and heart work normally with ketones as an energy source. This special diet must be strictly followed. Too many carbohydrates can stop ketosis. But some children become seizure-free when put on the diet. Vagus nerve stimulator. This treatment sends small pulses of energy to the brain from one of the vagus nerves.
This is a pair of large nerves in the neck. If your child is age 12 or older and has partial seizures that are not controlled well with medicine, VNS may be an option. VNS is done by surgically placing a small battery into the chest wall. Small wires are then attached to the battery and placed under the skin and around one of the vagus nerves. The battery is then programmed to send energy impulses every few minutes to the brain. When your child feels a seizure coming on, he or she may activate the impulses by holding a small magnet over the battery.
In many cases, this will help to stop the seizure. VNS can have side effects such as hoarse voice, pain in the throat, or change in voice.
Surgery may be done to remove the part of the brain where the seizures are occurring. Or the surgery helps to stop the spread of the bad electrical currents through the brain. Surgery for epilepsy seizures is very complex.
It is done by a specialized surgical team. Your child may be awake during the surgery. The brain itself does not feel pain.
If your child is awake and able to follow commands, the surgeons are better able to check areas of his or her brain during the procedure. Surgery is not an option for everyone with seizures.
If age-appropriate, make sure your child understands the type of seizure he or she has and the type of medicine that is needed. Know the dose, time, and side effects of all medicines.
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