Cardiac genetics

This information is designed for a person with a cardiovascular disorder who is considering genetic testing. The decision to have such testing should not be taken lightly. It is essential that the issue be discussed with an experienced medical specialist or genetic counsellor.

 

The purpose of a genetic test is to identify the underlying genetic error responsible for your cardiovascular disorder. If a genetic error is identified, this would indicate that your disorder is indeed familial, and that your relatives are at risk of carrying the same genetic error. Your relatives could then seek genetic testing if they wish. The identification of the underlying genetic error can also provide your medical specialist with more information to guide recommendations for your treatment. 

The heart pumps blood to the lungs and then to the body. Abnormalities in the heart or in the large veins and arteries taking blood to and from the heart are described as ‘cardiovascular disorders’.

Cardiovascular disorders can be due to:

>   Abnormal weakness of cardiac muscle (cardiomyopath)
>   Abnormal cardiac rhythm (arrhythmia)
>   Progressive abnormalities in the large arteries leading to the lungs (pulmonary hypertension) or to the rest of the body (aortic disorder)
  Other abnormalities in medium-sized arteries (vasculopathies)
>   Inherited high cholesterol (hyperlipidaemia) or abnormalities in cholesterol metabolism

In each case, the disorder can be due to a combination of inherited genetic errors, environmental factors and chance. The significance of genes, environment and chance will vary with different disorders and in different patients. 

A ‘familial cardiovascular disorder’ is a disorder that runs in the family due to an inherited genetic error. If an inherited genetic error is the major underlying cause of your cardiac disorder, the abnormal gene may have been inherited by your relatives. Relatives who have inherited the abnormal gene may also be at risk of developing the disorder. 

Cardiac genetic testing with Sonic Genetics involves having a blood sample collected from you, the affected person. The genetic material in your blood sample is then examined to identify an error in any one of the genes associated with your diagnosis. 

As the outcome of genetic testing may have medical and psychological implications for you and your family, we require pre-test genetic counselling and informed consent prior to testing. This is arranged by Sonic Genetics and is provided to you as part of your cardiac genetic test. 

Your doctor will tell you about the result of your test. If one or more genetic errors are found, your

Your doctor will tell you about the result of your test. If one or more mutations are found, your doctor will outline how this information explains your diagnosis and the medical implications for you and for your treatment.

The identification of a mutation paves the way for your relatives to have genetic testing to clarify their risk. This test is very accurate in determining the presence or absence of the family’s mutation. Of course, this testing is entirely voluntary. Genetic testing of an unaffected relative for such a mutation can raise a number of significant medical, psychological, legal, and financial considerations. For this reason, an Australian laboratory can only do such tests after the relative has had professional pre-test genetic counselling. Genetic counselling services are available in each state and territory of Australia.

If a mutation is not identified by the laboratory, you will be advised of this by your doctor. This result reduces the probability that your disorder is familial, but it does not exclude this possibility. Your doctor may still make recommendations regarding the medical care of your relatives. 

The price for a genetic test for cardiovascular disease is typically $1,000-$3,000. The current prices for our tests are provided here on this site. At this stage, these costs are not rebated by Medicare or private health insurers.

These tests are expensive because they involve exhaustive assessment of many different genes while the laboratory searches for the genetic cause for your cardiovascular disorder. Once a mutation has been found, relatives can be tested for the presence or absence of the specific mutation already identified in the family, and this is much cheaper. In other words, the expensive test need only be done once, and it potentially benefits many members of the extended family. Some families share the cost of testing with their relatives. 

Please direct any questions or concerns to your doctor. You can also find more information about genetic testing in general, about your cardiovascular disorder, and about our cardiovascular genetic tests, here on this website, as well as www.heartregistry.org.au. 

Costs will vary widely depending upon the tests required. This will need to be discussed with your doctor.

Sonic Genetics utilises our world-class genetic laboratories to provide you with an excellent genetic test. However, genetic testing for a heritable disorder involves more than good laboratory practice. The test result may also have broader implications for the person tested (e.g. insurance, family planning), as well as significant implications for family members (e.g. future health, insurance etc).

For these reasons, a careful discussion about the medical and non-medical implications of a genetic test for both the patient and relatives is recommended before the test is performed. This discussion is called “genetic counselling”.

For patients having a cardiac genetic test, Sonic Genetics is pleased to provide genetic counselling as part of the testing process. Genetic counselling is provided by telephone and at no additional cost.

Find out more about genetic counselling for cardiac genetic tests