A recent study sought to find how common genetic cardiomyopathies are in the general population.
By studying United Kingdom Biobank samples from 200,643 people who had undergone complete genetic sequencing, researchers established that genes linked to HCM are found in one out of every 149 people!
More than half of those identified as having a HCM gene had a mutation in the MYBPC3 gene, making it the most common HCM gene in this sampling.
A team of international genetic researchers has just won “The Big Beat Challenge” – a grant from the British Heart Foundation of £30 million ($36 million) payable over a 5 years period to study potentially curative gene therapies to treat genetic cardiomyopathies.
A group of scientists working on gene therapy for inherited cardiomyopathies are seeking input from patients about their interest and willingness to participate in gene therapy trials. These researchers hope that treatment with gene therapy will ultimately prove to be a cure for hypertrophic cardiomyopathy as well as other genetic cardiomyopathies.
If you are interested in learning more about gene therapy and are willing to answer a few questions about your willingness to participate in this type of research, watch this video. Then, fill out this short questionnaire. It just takes a few minutes and you may help to find a cure 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!
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.
A recent discovery by British researchers sheds light on how a type of common genetic mutation – a so called “common variant” – influences the expression of hypertrophic cardiomyopathy caused by mutation(s) in the cardiac sarcomere.
This research, funded by the British Heart Foundation and spearheaded by Dr. Hugh Watkins of the University of Oxford, explains why some individuals with a particular sarcomere mutation develop a severe case of HCM, while their family members with the same mutation may develop only mild HCM symptoms or show no signs of the disease at all. It also may explain why people who lack sarcomere mutations develop the disease.
The researchers compared the DNA of 2,780 people with HCM and 47,486 people without HCM and found that common variants acting in concert with rare sarcomere mutations determine whether a person will develop HCM.
In addition, the researchers found that HCM attributable to common variants alone is unlikely to be passed on to future generations. This is good news for the children of HCM patients caused by common variants.
Lastly, this paper found that high diastolic blood pressure was associated with the development of HCM caused by common variants. Hence, keeping blood pressure under control is something that patients can do to minimize their risk of developing HCM in the future.
The highly anticipated 2020 American Heart Association/American College of Cardiology Guidelines for the Diagnosis and Treatment of Patients with Hypertrophic Cardiomyopathy have been released.
This document, drafted with reference to published HCM literature, and with input from a committee of HCM experts with broad expertise, updates the prior version published in 2011. It contains clinical practice guidelines for the broad spectrum of issues which may confront medical professionals as they approach the diagnosis and treatment of patients and families affected by hypertrophic cardiomyopathy.
This story in the Wall Street Journal about genetic testing shows the speed of changes in the medical community’s understanding of how and whether certain genes cause hereditary disease.
The article quoted Dr. Jodie Ingles, a geneticist from the University of Sydney in Australia who specializes in HCM and has published a recent article on the subject. Dr. Ingles said that 22 out of 33 genes comprising a genetic testing panel commonly used to test for HCM had either limited or no evidence of being disease causative.
Continue reading “Wall Street Journal Highlights Risks in Genetic Testing”
A recent study published in Circulation suggests that clinical testing of kids who are first degree family members of HCM patients (i.e. siblings and children of those who have already been diagnosed with HCM) could be improved by starting testing at a younger age. And, genetic testing should further improve diagnosis and treatment for this group.
A recent study by several HCM genetics researchers around the globe, led by Australia’s Dr. Jodie Ingles, found that 2/3 of genetic mutations previously reported to patients as HCM causative may actually NOT trigger HCM.
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