Sabrina Cuddy • March 21, 2024
April’s Topic is Genetic Testing

Who should have genetic testing, why, and when?

Suppose you have been clinically (through an EKG, echocardiogram, and a visit with a cardiologist) diagnosed with HCM. In that case, most experts recommend that you have genetic testing to determine the underlying reason your heart is too thick.

Why does it matter?   

Some hearts look like HCM but have a specific genetic mutation for one of the HCM spectrum disorders – Amyloidosis, Fabrys, Danon, Sarcoidosis, etc. These disorders are often managed differently from HCM alone, so you need to know if you have one.

HCM is mainly caused by gene mutations (sometimes called variants or markers). Not all HCM is linked to a specific variant, and we believe more mutations will be identified in the future. 

In recent studies at large HCM Centers, about 40% of those tested had a gene mutation known to cause HCM. As of 2023, 60% will not have a mutation currently identified as causing HCM. It is still believed that HCM is a genetic disorder that families can pass down – even if the mutation is currently unknown. 

Your genetic test can show one of three results:

  • Positive / Mutation identified (you have a known variant). 
  • Negative / No mutation identified (you do not have a known variant).
  • VUS (a variant of uncertain significance whose meaning is still evolving). It’s a bit confusing, but as researchers learn more, a VUS can be reclassified as a positive or negative.

If your genetic test is positive, this information can be used to screen family members to see if they have the same variant.  Your children, parents, and siblings can be tested for your variant, and if they don’t have it, they can skip clinical tests (echocardiogram, etc.) unless they develop heart symptoms. 

A negative genetic test DOES NOT take away your HCM diagnosis ,  and it DOES NOT mean that your family can safely avoid clinical screening for HCM  (echocardiogram, EKG, and an exam by a cardiologist). Researchers are still discovering variants that may cause HCM and are starting to look into combinations of two or more genetic variants ( polygenetic ) that could cause HCM. If you do not have a known variant, your close relatives must be screened regularly using clinical tests to see if they develop HCM. 

Once you’ve gone through our free  Intake  process, we will invite you to join our new  Nest  education program.  For a great explanation of genetic testing in HCM, sign up for the Nest portal when you’re invited.

Knowing your mutation may allow gene therapy to treat your HCM in the future. Clinical gene therapy trials for those with a mutation on MYBPC3 have started! We expect other common HCM variants (such as MYH7, etc.) to be included in future clinical trials.

A last thought: many people who test positive for one of the known variants say, “I have the gene for HCM,” but this is misleading. They have a mutation on one of many genes that may contribute to HCM.For more information about genetics and genetic testing, please visit the HCMA website at  https://4hcm.org/genetic-testing-an-overview/  and  https://4hcm.org/genetic-testing-other-considerations/.

HCMA Blog

By Lisa Salberg July 3, 2025
Summer, greetings to all our big-hearted friends As July approaches, our focus is already on the fall and preparing for some major events, including our annual meeting coming up in October. July will also find us on the west coast in Seattle conducting a regional patient education meeting as part of our big-hearted warrior tour. We have been following the generic drug quality issue in the United States very closely and encourage you to watch the series starting with our Hill briefing in April and following with the additional webinars with our partners at Medshadow and the People's Pharmacy, and of course the ProPublica series of articles. See them all here . We are happy to have a new team member on board - we welcome Pam as our coordinator of both our All Hearts Collaborative and Hearts and Minds project. Over the next few months, you're going to be learning more about these two amazing initiatives and how we are working to provide better services for big hearts regardless of where you live, so we are meeting all of our big-hearted friends where they are. Please stay tuned for updates from these projects coming soon. We are also creating new volunteer opportunities and engagements that we hope will make it easier for you to participate in spreading the message of the importance of diagnosis, the importance of community readiness related to CPR and AED use and, of course, helping patients get to their ultimate diagnosis and getting them on the proper treatment pathways. This July I would like to recognize all of the special birthdays in my family, including HCMA Center of Excellence coordinator, Stacey Titus-brown and my daughter Rebecca Salberg. It's a milestone birthday for Becca - it’s hard to believe I have a 30-year-old child. Wishing you all a happy and healthy summer. Go build some memories!
An official seal in black  & red with white letters that say HCMS Recognized Centers of Excellence
By Sabrina Cuddy July 3, 2025
Getting HCM care at a HCMA Recognized Center of Excellence has a positive impact on patient's outcomes. Find out why in the post by Health Educator Sabrina Cuddy
By Erica Friedman June 26, 2025
Investigative journalists Debbie Cenziper, Megan Rose, Brandon Roberts and Irena Hwang from Pro Publica and NPR have concluded a 14-month long investigation into the quality of generic drugs coming into the United States from overseas. Among the many voices that spoke up for American patients was HCMA Founder and CEO, Lisa Salberg who has felt the effects of low-quality drugs personally. Salberg believes that fixing this problem is something we can do, even in this time, when even health care is highly politicized. Read the key takeaways from ProPublica’s 14-month investigation into the FDA’s oversight of foreign drugmakers in Threat in Your Medicine Cabinet: The FDA’s Gamble on America’s Drugs .
More Posts