Targeted Gene Therapy for HCM

The expanding field of personalized medicine has not left hypertrophic cardiomyopathy behind. In fact, two companies are currently developing targeted gene therapies for HCM patients. Each therapy targets a separate and distinct HCM gene mutation.

Tenaya Therapeutics, located in the San Francisco area, is developing a therapy called TN-201 which is directed at mutations in the Myosin Binding Protein C3 (MYBPC3) gene. The therapy has shown favorable results in mice.  In May of this year, Tenaya received Orphan Drug Designation from the U.S Food and Drug Administration. An Orphan Drug Designation confers certain tax and economic incentives on companies developing a treatment for rare conditions.

Meanwhile, this week, Lexeo Therapeutics acquired Stelios Therapeutics, a San Diego based company developing a therapy for HCM patients with a mutation in the TNNI3 gene. These TNNI3 patients comprise somewhere between 5% and 7% of all patients with HCM, or approximately 30,000 people.  The underpinnings of this research come from the University of California, San Diego.

HCMBeat will continue following these developments. It is a busy and exciting time in the treatment of HCM!

Identical Twins Show Impact of Behavior and Environment on HCM

A recent study of identical twins with HCM found significant variation in the expression of hypertrophic cardiomyopathy, even between twins carrying the same HCM-causing genetic mutation. 

This paper concludes that epigenetics (things which influence expression of DNA like behavioral and environmental factors) greatly influence the expression of HCM genetic mutations. 

The researchers studied 11 pairs of twins with HCM. 9 of the twin pairs had known HCM sarcomere mutations while 2 of the pairs had HCM of unknown cause. The siblings were followed for a time frame of between 5 to 14 years.

Researchers compared left ventricular wall thickness, left atrial size and left ventricular ejection fraction. Differences were found in the left ventricular wall thickness of all 11 pairs of twins, while left atrial size was similar in 3 of the 9 twin pairs who carried HCM mutations. Left ventricular ejection fraction was different in 4 of 7 twin pairs. 

The researchers theorize that similarities in left atrial size may be due to impaired ventricular relaxation directly tied to sarcomere dysfunction. In contrast, environmental factors yield more influence over ventricular function.

HCM epigenetics is a field ripe for research. As HCM patients, we hope that it will yield actionable data in the near future.

Are HCM Kids With MYH7 Gene at Increased Risk?

A recent Canadian study found that children with HCM who carry a single mutation in the MYH7 gene or who have multiple HCM-causative genetic mutations are at increased risk of major adverse cardiac events when compared to children who carry a single mutation in another gene.

Of the 98 gene positive children in this study, those with a MYH7 mutation or those with multiple mutations were more likely to need a myectomy or an ICD or to experience a sudden cardiac arrest or a heart transplant when compared to children with other HCM causative mutations.

The article also suggests that current screening protocols which recommend clinical and genetic screening for HCM beginning at age 12 may be insufficient.

Do Elite Athletes Provide Clues About HCM?

 

During the Olympics we all gather around our television sets to watch the best athletes in the world compete against each other and we wonder how it is that they can humanly perform at such a high level?

This feature story about Stanford HCM Clinic’s Dr. Euan Ashley provides us with an interesting overview of the research Dr. Ashley is doing on high performance elite athletes with the hope that their genes may provide clues that will one day help to help treat those of us with HCM and other genetic heart conditions.

HCM GENOTYPE DOESN’T INFLUENCE ATRIAL FIBRILLATION

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openclipart.org 6/25/16

 

In the April edition of the American Journal of Cardiology, Italian HCM experts published their findings which indicate that  an individual patient’s HCM causing gene does not influence chances of developing atrial fibrillation and shouldn’t influence the management strategies for the condition.