How Genetic Testing Helps - Diagnosis & Treatment

If you are diagnosed with an inherited arrhythmia and no one in your family has been genetically tested, genetic testing can help in two ways:

       1) identify your family mutation to help your other relatives know the “family gene”, and
       2) help your doctor guide the treatment for your specific gene mutation.
Knowing your mutation can affect which medication is chosen and contribute to the decision of whether or not to recommend an ICD.

If your diagnosis is unclear and your family mutation (variant) is known, genetic testing can help clarify whether or not you have an inherited arrhythmia. Parents, siblings, and children (or future children) can also be tested for the "family mutation" to see if they need to be treated.

If your diagnosis is unclear and no one in your family has been genetically tested, genetic testing can be done on a person in your family that has already been diagnosed, or the person who has the strongest likelihood of having a SADS condition. If they test positive, then you can be tested for their mutation – because it is considered your “family mutation (variant)”.

If you (or a family member) tested negative with genetic testing, it could mean any of the following:

• You still have a SADS condition but your mutation has not been discovered yet (e.g., this is true for 25% of confirmed LQTS patients whose EKGs, symptoms, and family history are sufficient to make the diagnosis)
• You may have a different SADS condition than the specific one you were tested for
• You may not have a SADS condition

But this needs to be determined very carefully by a knowledgeable physician because there are many people with LQTS and other inherited arrthymias who may be "concealed" on a resting EKG and whose genetic mutation has not been discovered - so they test negative with genetic testing.

There are several commercial CLIA-certified labs from which your physician can order your genetic test. As with any healthcare service, it is always a good idea to be a wise consumer and research each company to see which one might be the best choice for you.

Who should be tested?

• All patients receiving a clinical diagnosis of a SADS condition from their physician
• Family members of a person with a known pathogenic or likely pathogenic variant in their family. Confirming the presence or absence of the  "family mutation (variant)" is a less expensive, limited test done rather than extensive clinical testing (ECG, EP study, etc.)
• Anyone who was tested in a research study or more than 3-5 years ago.

How can I get tested?

Your doctor needs to order this test just like any other medical test. We recommend that you be evaluated by an electrophysiologist or a cardiologist who can then order the test. If you need a physician, we have a list of physicians around the country.The costs of genetic testing are minimal now, or even free! Insurance providers generally cover the cost.

What are the steps to get tested?

1. Meet with a genetic counselor or your doctor to discuss the genetic testing process and obtain a blood sample or a saliva sample or a cheek swab.
   
2. About 4-6 weeks after sending your sample, your doctor and team will receive the results.
3. You should then meet with your genetic counselor or doctor to discuss these results and get a copy of the report. (You should always ask to receive copies of your ECGs, test results, etc.)
4. If your test results come back positive, it is very important to discuss having other family members tested.

Invitae Detect Program

The Detect Cardiomyopathy and Arrhythmia Program is a sponsored, no-charge genetic testing and counseling program for individuals suspected of having a familial cardiomyopathy or arrhythmia. Invitae's mission is to make high quality genetic testing accessible to all who need it.

To learn more about no-charge genetic testing click HERE

Genetic Testing Companies:

Invitae
www.invitae.com
Testing inquiries 415-374-7782

Ambry Genetics
www.ambrygen.com
Client Services 949-900-5500

Blueprint Genetics
www.blueprintgenetics.com
Customer Support 650-452-9340

Gene Dx
www.genedx.com
301-519-2100

Prevention Genetics (also has a DNA banking program)
www.preventiongenetics.com
715-387-0484

What about other family members and testing?

Your doctor will be able to help you determine if other family members should be tested. In general, if your test is positive, your children, siblings, and parents should be tested, too. This means they will have an ECG and then be tested for your specific mutation. This test is less expensive than the initial test.

Based upon the test results of your close family members, others in your family (grandparents, aunts/uncles, nieces/nephews, etc.) may need to get tested, too. You should compile a family health history for your extended family in order to make sure that a physician evaluates everyone who might be at risk for your SADS condition.