Genetics and epilepsy
At a glance
What are genes?
Our genes tell our body how to develop and function. They are passed on to us from our parents, but we each have our own combination of genes and this makes us all different.
Sometimes genes can have changes, called mutations. Some mutations may cause health problems. When gene mutations are passed down from parents to children, this is known as ‘inheritance’.
‘The Gene People’ have a Beginners Guide To Genetics with more information about how gene mutations are inherited.
Health problems caused by changes to genes are not always inherited. Children can have genes that are different to their parents. When a change to a gene is seen for the first time in a child, this is called a ‘de novo mutation’. This means ‘new mutation’. If a child has a new gene mutation, this may cause them to develop a genetic health problem, even when no one else in the family has it.
Is my epilepsy caused by my genes?
Knowledge about epilepsy, genes, and genetic testing techniques, are developing all the time. Researchers have identified a number of genes that are linked to epilepsy.
However, it is still a complicated picture. There can be several genes as well as other factors involved in causing epilepsy.
Your epilepsy specialist can tell you if your epilepsy may have a genetic cause. They may refer you for genetic testing.
The National Institute for Health and Care Excellence (NICE) recommends genetic testing for certain people, for example, if epilepsy started before the age of 2 years or if you have other features that might suggest a genetic cause for your epilepsy.
Even if your epilepsy is thought to have a genetic cause, it is not always possible to identify that cause. In around half of people with epilepsy there is no known cause for their seizures. Technology is constantly improving so researchers are likely to uncover the causes of seizures in more and more people over time.
Who is affected?
Some people have a genetic medical condition that includes epilepsy as a symptom. A few examples of these are listed below:
Tuberous sclerosis
This is a genetic condition that causes non-cancerous growths affecting many organs, including the brain. Epilepsy is a common symptom of tuberous sclerosis. More information is available from the Tuberous Sclerosis Association.
Fragile X syndrome
This is caused by a gene mutation on the X chromosome. It causes a wide range of difficulties with learning, and around 13% of males and 6% of females have seizures. More information is available from the Fragile X Society.
Rett syndrome
Rett syndrome is a rare genetic disorder that affects brain development, often resulting in severe mental and physical disability. It is estimated to affect about 1 in 10,000-12,000 girls born each year and is only rarely seen in boys. More information is available from Rett UK.
Neurofibromatosis 1 (NF-1)
Neurofibromatosis type 1 (NF1) is a genetic condition that causes tumours to grow along your nerves. The tumours are usually non-cancerous (benign) but may cause a range of symptoms, including epilepsy. More information is available from Nerve Tumours UK.
Epilepsy syndromes
Some epilepsy syndromes are more likely to be caused by genes. A syndrome is a group of signs and symptoms that, added together, suggest a particular medical condition.
Examples of epilepsy syndromes that are thought to have a genetic cause include:
- Childhood absence epilepsy (CAE)
- Juvenile myoclonic epilepsy (JME)
- Genetic epilepsy with febrile seizures plus (GEFS+)
Our website has more information about epilepsy syndromes.
Facts
Research into epilepsy and genetics is being carried out all the time to try to find out more about which genes might cause epilepsy and which ones are likely to be inherited.
Here are the main things that we understand so far:
- Some children are born with changes to specific genes that cause them to develop epilepsy
- Sometimes these changes are inherited from their parents, and sometimes they happen on their own
- Some types of epilepsy have a higher risk of being inherited than others
Questions you may have
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What is genetic testing?
Genetic testing for epilepsy is usually done using a sample of your blood. The sample is sent to a laboratory to be analysed. The test looks at your genes to see if there are changes that might cause epilepsy.
Before having genetic testing, you should discuss what the results might show and the possible implications with a doctor. You might also want to think about how much information you want to know, and whether it would be helpful to you.
Information about genetic testing and counselling is available on the NHS website.
Having a type of epilepsy that is linked to your genes does not always mean that it is inherited as the cause could be due to a new genetic mutation.
It can also be useful to talk to a genetic counsellor or your epilepsy specialist once you have your results, to help explain what they mean for you and your family, or any children that you may have.
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What kind of results can I expect from genetic testing?
Gene change found (positive test result)
- If a gene change is found, this means that the cause of the person’s epilepsy is genetic
- This can be helpful if you are thinking about having a family. It can help you to understand how the gene might affect other family members or future children. There may be an option for having a genetic test while pregnant for some families if they wish
- Finding a gene change might also give you more information about the condition and how it could change over time.
No gene change found (negative test result)
- If no gene change is found, this does not mean there isn’t a genetic cause for your epilepsy. It means that one hasn’t been found with this particular test.
- Genetic testing is constantly improving and there may be more genetic tests available in the future.
Uncertain Test Result
- An uncertain test result can mean a gene change has been found, but the laboratory are not clear if this is the answer for your epilepsy or not.
- Over time, there may be more information about this type of uncertain result.
Unexpected Results
- With some types of genetic testing unexpected gene changes can be found.
- Genetic testing will look at lots of different genes. It is possible that a medically important condition is found, but isn’t related to epilepsy.
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How will genetic testing benefit my epilepsy?
Genetic testing can help to identify the cause of a person’s epilepsy, sometimes giving a more accurate diagnosis and better management. Genetic testing can have a positive impact on your epilepsy diagnosis and treatment. The results can help medical professionals choose the best treatment and decide whether any further investigations are needed. It can be very helpful for people who have a genetic epilepsy disorder and do not have seizure control.
At the moment, most genetic epilepsies do not have a specific treatment which works for them. But research is happening all the time and hopefully more targeted treatments will be available in the future.
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How could genetic testing affect my family?
Genetic test results could also be important for other people in your family. In some cases, family members might ask for a referral to clinical genetics, especially if there is a known genetic change in their family. This often happens when people are planning a family or are pregnant.
It is important to be aware that genetic testing can also give information about your relatives and their relationship to you.
You can find out more information on the possible benefits and risks on the following website from the Genetic Alliance.
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What is the risk of my child inheriting epilepsy?
Most children of people with epilepsy do not develop epilepsy.
However, each type of epilepsy has a different level of risk for being inherited.
The level of risk will depend on things such as how many other family members have epilepsy, the type of epilepsy you have, and the age it started. For example, there is thought to be a slightly higher risk for parents that have a generalised rather than focal type of epilepsy passing this onto their children.
It is not always straightforward to predict who will develop epilepsy, as a child can be seizure free even if both parents have epilepsy.
But when both parents have changes in the same genes that have been linked to epilepsy, the chance of epilepsy in their children is increased. If you have questions about the risk of your child inheriting epilepsy you can talk to your epilepsy specialist and discuss the possibility of genetic testing.
More information
The NHS website
The NHS has more information about Genetic and genomic testing.
Gene People
The genetic conditions support group.
Helpline: 0800 987 8987
Contact – for families with disabled children
Helpline: 0808 808 3555
Got any questions?
Our expert advisors can help you with any questions you might have about epilepsy and genetics or anything else related to living with epilepsy.
