You inherit a lot of things from your parents, including the color of your eyes and how tall you will be. But not every genetic trait is a good one.

An arrhythmia is one example of a genetic health condition. These can also be called inherited or familial conditions.

While sudden cardiac death is extremely rare, affecting just 3 in every 100,000 people, a 2011 study found that about 70 percent of people under 40 who died from sudden cardiac issues had underlying heart arrhythmias that they inherited. This means that the issue with the hearts ability to beat regularly was passed on by one or both parents.

Sometimes, the issue is limited to a malfunction in the electrical signals in the heart, the American Heart Association says. But in about a third of cases, arrhythmias can develop because of structural issues, or the way the heart is formed.

Your heart operates using a complex electrical system that pulses through a detailed and delicate structure. Any time one of these electrical signals is off, or a part of the structure is damaged or formed incorrectly, it can create a host of issues.

Experts divide inherited heart arrhythmias into two categories:

All inherited heart arrhythmias are considered to be relatively rare conditions, but the most common types are:

Read on to learn about the main types of inherited heart arrhythmias.

Atrial fibrillation, also known as AFib or AF, is the most common type of heart arrhythmia overall. This condition involves the top chambers of the heart, which are known as the right and left atria.

In AFib, the right and left atria quiver and are not coordinated in pumping. This leads to compromised blood flow to the lower chambers of the heart, or the right and left ventricles.

AFib can cause blood to pool in the atria. This increases your chance of developing blood clots, which are potentially life threatening. A 2016 study estimated that up to a third of all strokes that occur in people ages 65 and older are due to AFib.

This condition can develop with age, but recent studies have found that up to 30 percent of people with AFib inherited it. According to MedlinePlus Genetics, several genes have been linked to the development of familial AFib:

Many of these genes provide instructions as your heart forms on how its electrical channels should be wired. If these channels arent wired correctly, then ions tiny particles with an electrical charge will have trouble passing signals through the muscles of your heart.

Brugada syndrome is another type of electrical issue in the heart that causes the ventricles to beat irregularly or too fast. When this happens, your heart cant pump blood out to the body effectively.

This can cause serious difficulties since many of your organs rely on a consistent and strong blood flow to work properly. In severe cases, Brugada syndrome can cause ventricular fibrillation, a potentially life threatening irregular heart rhythm.

A 2016 study showed that at least 23 genes are associated with this syndrome. The primary ones are:

This is a rare form of inherited arrhythmia. People with catecholaminergic polymorphic ventricular tachycardia (CPVT) will experience a very fast heart rhythm during physical activity, called ventricular tachycardia.

In CPVT, ventricular tachycardia usually happens during some form of exercise. Sometimes you can notice it before ventricular tachycardia occurs. You can do this by observing symptoms known as ventricular premature contractions (VPCs) during exercise.

With this type of genetic arrhythmia, the structure of the heart is usually unaffected. It typically appears in people 40 years and younger.

Specific genes linked to this condition are:

MedlinePlus Genetics says that RYR2 mutations account for about half of CPVT cases, while CASQ2 causes only about 5 percent. Both these genes are responsible for making proteins that help keep your heartbeat regular.

With this condition, the muscles that cause the heart to contract, or beat, take too long to recharge between pumps. This can upset the timing and regularity of your heartbeat, leading to other issues. While long QT syndrome can be caused by medications or other heart conditions, it can be inherited for many.

A 2016 study found that 15 genes are associated with this condition, but the most common are:

Most of the genes linked to familial arrhythmias are autosomal dominant, but some autosomal recessive disorders can cause long QT syndrome too. Genes KCNQ1 and KCNE1 are linked to rarer types of long QT syndrome called Jervell and Lange-Nielsen syndromes. In addition to inherited arrhythmias, people with these conditions also experience deafness.

This is an uncommon type of inherited arrhythmia. According to MedlinePlus Genetics, only about 70 cases of short QT syndrome have been diagnosed since it was recognized in 2000. Many more cases may exist, but they havent been diagnosed because this syndrome can occur without any symptoms.

With this condition, the heart muscle doesnt take long enough to charge between beats. This can cause no symptoms at all in some people. But in others, its the cause of sudden cardiac arrest or death.

Genes linked to this condition include:

With this rare condition, the heart has both structural and electrical issues. Electrical issues come in the form of a long QT interval, or the time it takes the heart to charge after each beat.

A long QT interval can lead to ventricular tachycardia, an often fatal arrhythmia. Ventricular tachycardia is the cause of death in about 80 percent of people with this syndrome.

Since this syndrome can also affect other parts of the body like the nervous system and immune system, many people with Timothy syndrome die during childhood. Its an autosomal dominant syndrome, meaning only one copy of an altered gene can lead to it. But because few people with Timothy syndrome survive into adulthood, its not usually passed from parent to child.

Instead, Timothy syndrome usually develops because of new mutations in the CACNA1C gene. This gene helps to manage the flow of calcium ions through heart muscles, affecting the regularity of your heartbeat.

Another issue with the hearts electrical system, Wolff-Parkinson-White syndrome occurs when an extra pathway for signals forms in the heart. This means that electrical signals can skip over the atrioventricular node, the part of the heart that helps control your heart rate.

When electrical signals skip over this node, it can cause your heart to beat extremely fast. This results in an arrhythmia called paroxysmal supraventricular tachycardia.

In some cases, this syndrome has been passed on through families. But most people who develop this condition have no family history. Also, for many people with this syndrome, the cause is unknown. A few cases are the result of mutations in the PRKAG2 gene.

This rare condition is primarily a structural issue. If you have this condition, a genetic mutation causes the muscle cells in your right ventricle the lower chamber of the heart to die. The condition mostly develops in people under age 35.

Arrhythmogenic right ventricular dysplasia usually develops with no symptoms at all. But it can still cause irregular heartbeats and even sudden death, especially during exercise. In later stages, this condition can also lead to heart failure.

Roughly half of all cases of arrhythmogenic right ventricular heart failure run in families. Autosomal dominant transmission from one parent is most common. But it can be passed on as an autosomal recessive gene from both parents, too. At least 13 genetic mutations have been connected to this disorder. PKP2 appears to be one of the most commonly affected genes.

Genes that cause this condition are responsible for forming desmosomes, or structures that connect muscle cells in the heart to each other. When these cells are not formed correctly, the cells that make up the muscles in your heart cant connect or communicate signals to one another.

Theres a lot of uncertainty around the cause of idiopathic ventricular fibrillation. Many people who are diagnosed with this condition have survived a cardiac arrest with ventricular fibrillation and no other obvious causes. A genetic cause has been proposed in a 2016 study, but research is ongoing.

Idiopathic means that a conditions origins are unknown. As genetic testing for other familial arrhythmias improves, it seems as though cases of idiopathic ventricular fibrillation are going down.

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Arrhythmia: Is It a Genetic Condition? - Healthline