Did you know that 30 percent to 40 percent of epilepsy cases are genetic? Some people inherit forms of epilepsy passed down from parents to their children. Others develop spontaneous genetic changes without any family history of epilepsy.

In addition to genetics, environmental factors can also contribute to epilepsy. Brain trauma (head injury), infections, and structural changes in the brain (such as tumors or stroke-related damage) can all play a role. In some cases, the cause remains unknown.

In this article, we’ll discuss inherited genes that can lead to epilepsy and other possible causes.

Is Epilepsy Genetic?

Research shows that some types of epilepsy are related to genetics.

DNA contains genes that provide instructions for making proteins. Some mutations (changes or variations) in genes can increase a person’s risk of developing epilepsy.

These variations are usually in genes that control how neurons (nerve cells) communicate in the brain. Changes in these genes can disrupt normal signaling and lead to bursts of electrical activity in the brain, which may cause seizures.

About 30 percent to 40 percent of epilepsy cases are related to genetic factors. These genetic traits can be passed from parents to their children. This means that people with a family history of epilepsy may have a higher risk of developing it. Having a parent or sibling with genetic epilepsy means you’re about two to four times as likely to have the same condition.

About 30 percent to 40 percent of epilepsy cases are related to genetic factors.

However, many people with these gene changes will never have seizures or develop epilepsy. This means that genetic factors are only one part of the picture. Other factors, such as environmental influences, can also play a role. These can include brain injuries, infections, and stroke.

Some children develop new (spontaneous) genetic variations that lead to epilepsy. These spontaneous (de novo) variations aren’t passed down through families. The parents of these children typically don’t carry the variations or have a family history of epilepsy. These changes can happen in the egg or sperm before or at the time of conception (when pregnancy begins).

Children with random genetic variations that cause epilepsy may have:

• Seizures that are hard to control with standard anti-seizure medications (sometimes called treatment-resistant epilepsy)
• Differences in brain development (sometimes called structural brain changes or birth differences)
• Other neurodevelopmental symptoms (conditions that affect brain development), such as developmental delays

What Genes Are Involved in Epilepsy?

Doctors can classify (group) genetic epilepsy based on the affected genes. There’s no single variant that causes epilepsy. Instead, we know that nearly 1,000 genes may be involved.

Examples of epilepsy caused by specific gene variations include:

• Angelman syndrome — Linked to changes in the UBE3A gene
• Rett syndrome — Linked to changes in the MECP2 gene
• Dravet syndrome — Linked to changes in the SCN1A gene
• Glucose transporter type 1 (GLUT1) deficiency syndrome — Linked to changes in the SLC2A1 gene
• Lennox-Gastaut syndrome — Linked to several gene variations, including SCN1A, CHD2, and FOXG1
• West syndrome — Linked to changes in the CDKL5 and ARX genes

These are just a few of the many genetic epilepsies. Researchers are still finding new genes involved in seizure disorders. As scientists learn more, this research may help guide more personalized treatments and improve care for people living with epilepsy.

Can You Do Genetic Testing for Epilepsy?

Overall, parents with epilepsy rarely pass the condition directly to their children. There’s a 2 percent to 5 percent chance of this happening.

If you’re concerned about genetic epilepsy, you may want genetic testing. A simple blood test can look for gene variations linked to epilepsy and other health conditions.

If you have a family member with epilepsy, genetic testing can also reveal whether you carry a variation. You can have a gene variation without having epilepsy yourself. Testing can help you better understand your chances of passing a genetic variation to future children.

What Are Other Causes of Epilepsy?

Aside from genetic causes, epilepsy can develop from brain injury, underlying health conditions, or other factors that affect how the brain works. Changes in the brain’s structure, trauma, and inflammation can all play a role in the development of epilepsy.

1. Congenital Birth Defects and Prenatal Damage

Some babies are born with conditions present at birth (called congenital conditions) that affect brain structure and function. While a baby is developing in the womb, they are very sensitive to changes in their environment.

Certain health problems during pregnancy can affect a developing baby. These include:

• Low oxygen levels
• Infections
• Poor nutrition

Babies born early and those with low oxygen at birth can also have brain damage. This may increase the risk of seizures and epilepsy later in life.

Babies born early and those with low oxygen at birth may have brain damage that leads to the development of epilepsy.

Abnormalities in the brain’s structure can also increase the risk of seizures. For example, malformations in the brain’s blood vessels can raise the risk for epilepsy.

An arteriovenous malformation (AVM) is a condition that causes tangled blood vessels. These vessels can reduce normal blood flow and oxygen delivery to brain tissue. The abnormal blood vessels can also burst, causing a hemorrhage (brain bleed).

2. Head Injuries

Brain injury from head trauma can cause epilepsy. A traumatic brain injury occurs when a sudden force or impact affects the head and brain.

Traumatic brain injuries can develop from:

• A sudden impact, like a car accident or a fall
• A skull fracture, which can put pressure on or directly injure brain tissue
• An object penetrating the skull, like a gunshot wound
• Violent shaking of an infant or young child (sometimes called abusive head trauma)

Seizures and epilepsy can develop after a traumatic brain injury. In some cases, seizures happen soon after the injury. In others, they may develop days, weeks, or even longer afterward.

3. Brain Tumors

Brain tumors are abnormal masses of cells that can press on or disrupt normal brain function. Tumors can irritate brain tissue and trigger seizures.

Epilepsy can develop in people with both cancerous and benign (noncancerous) brain tumors. For some people, seizures may be one of the first signs of a brain tumor. The type of symptoms a person has may help doctors understand which area of the brain is affected.

People with brain tumors may have different types of seizures. For example, some have focal seizures and epilepsy that develop near the tumor. Tonic-clonic seizures can occur if the tumor spreads to both sides of the brain.

4. Stroke

Strokes are a common cause of new epilepsy in older adults. It’s not always clear why epilepsy develops after a stroke. However, recent research suggests that changes in brain cell pathways and a buildup of harmful substances may play a role.

In general, damaged brain tissue can cause abnormal electrical activity, leading to seizures.

5. Metabolic Disorders

Epilepsy is linked to more than 750 types of metabolic disorders (conditions that affect how the body processes nutrients and energy). These disorders affect how the body uses and breaks down food.

Our brains need a form of sugar called glucose to work properly. We also need proteins, fats, and vitamins for our overall health. When metabolic disorders disrupt how the brain gets or uses energy, they can trigger abnormal electrical activity and increase the risk of seizures and epilepsy.

6. Infections

According to the Epilepsy Foundation, infections are likely the most common cause of epilepsy globally.

Infections can cause inflammation (the body’s response to fighting harmful germs like viruses and bacteria). In some cases, this inflammation can damage brain tissue and increase the risk of seizures and epilepsy.

Globally, infections are among the most common causes of epilepsy.

Examples of infections known to cause seizures and epilepsy include:

• Bacterial meningitis (may cause seizures during infection or lead to long-term complications)
• Human immunodeficiency virus (HIV)
• Malaria
• Tuberculosis
• Viral encephalitis, which causes brain swelling

7. Unknown Causes

Sometimes, healthcare providers can’t find a clear cause for epilepsy. This is called cryptogenic epilepsy (epilepsy with no identified cause). In many cases, the exact cause remains unknown, even after testing. About 50 percent of people with epilepsy may fall into this category.

As medical testing improves, doctors hope to better understand the underlying causes of these seizures and identify factors that were previously unclear.

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