Brugada Syndrome (BrS)

Brugada syndrome is a heart condition that causes a disruption of the normal rhythm in the heart’s lower chambers (ventricular arrhythmia). Signs and symptoms usually develop in adulthood but the diagnosis may be made at any age. Symptoms and complications often occur during rest or sleep, and may include fainting, seizures, difficulty breathing, or sudden death. The underlying genetic cause of inherited forms of Brugada syndrome is not known in most cases, but in up to 20-30% of people with Brugada syndrome, it is caused by a genetic change in the SCN5A gene. A number of other genes have been reported to be associated with Brugada syndrome in the literature, but the role they play in causing Brugada syndrome remains to be clearly defined. The genetic form of Brugada syndrome typically is inherited in an autosomal dominant manner. An acquired (nongenetic) form has been associated with certain drugs; abnormally high blood levels of calcium or potassium; or very low levels of potassium. In some cases, the cause of Brugada syndrome is unknown.

Genetic Mutations: Brugada syndrome is caused by genetic mutations, also known as pathogenic variants. Genetic mutations can be hereditary, when parents pass them down to their children, or they may occur randomly when cells are dividing. Genetic mutations may also result from contracted viruses, environmental factors, such as UV radiation from sunlight exposure, or a combination of any of these.

If you suspect you may have this disease, you may want to start collecting your family health history. Information such as other family members who have had similar symptoms, when their/your symptoms first appeared, or exposures to any potential disease-causing environmental factors should be discussed with your medical team.

Known Genetic Mutations: Brugada syndrome is caused by genetic mutations in the following known gene(s):

SCN5A, SEMA3A, SLMAP, CACNA1C, SCNN1A, SCN2B

Given these known genetic mutation(s), you may want to ask your health care team if genetic testing is right for you. Genetic tests are laboratory tests that use samples of blood, saliva, or other tissues to help identify changes in genes, chromosomes, or proteins. Genetic testing can help confirm or rule out a suspected genetic disease, or can provide other useful information to your health care team.

Yes. It is possible for a biological parent to pass down genetic mutations that cause or increase the chances of getting this disease to their child. This is known as inheritance. Knowing whether other family members have previously had this disease, also known as family health history, can be very important information for your medical team.

There are multiple ways, or patterns, a disease can be inherited depending on the gene(s) involved. Based on GARD’s current data, this disease can be inherited in the following pattern(s):

Autosomal Dominant: Autosomal means the gene involved is located on one of the numbered chromosomes. Dominant means that a child only needs to inherit one copy of the mutated gene, from either biological parent, to be affected by the disease.

People affected by an autosomal dominant disease have a 50% chance of passing on the mutated gene to their biological child.