In a new study published in the journal Circulation, researchers from Penn Medicine and Geisinger reviewed TTN (titin) gene sequences of more than 70,000 people, and found that 95 percent of patients who had the genetic mutations did not have heart disease or signs of cardiac decline. However, they did find subtle differences in the hearts ability to pump efficiently, compared to those without the mutation.
The USA’s first hospital was Pennsylvania Hospital founded in 1751 and the nation’s first medical school was founded at the University of Pennsylvania in 1765. Penn Medicine consists of the Raymond and Ruth Perelman School of Medicine at the University of Pennsylvania and the University of Pennsylvania Health System, which together form a $7.8 billion enterprise. Penn Medicine has pioneered medical frontiers with a staff comprised of innovators who have dedicated their lives to advancing medicine through excellence in education, research and patient care.
Founded in 1915, Geisinger is an integrated health services organization widely recognized for its innovative use of the electronic health record and the development of innovative care delivery models such as ProvenHealth Navigator®, ProvenCare® and ProvenExperience®. As one of the nation’s largest health service organizations, Geisinger serves more than 3 million residents throughout 45 counties in central, south-central and northeast Pennsylvania, and also in southern New Jersey at AtlantiCare, a Malcolm Baldrige National Quality Award recipient. In 2017, the Geisinger Commonwealth School of Medicine and Geisinger Jersey Shore Hospital became the newest members of the Geisinger Family. In addition, Geisinger has a long-standing commitment to medical education, research and community service.
Mutations in TTN, which affect about 1 percent of the global population, are commonly found in people with dilated cardiomyopathy. In this new study, researchers sought to determine if pinpointing the mutations could predict whether people carrying the faulty genes would develop the disease.
To do so, researchers reviewed the exome sequence data of 61,040 people in the Geisinger MyCode Community Health Initiative and 10,273 from the Penn Medicine BioBank to identify individuals with the gene mutations. From there, they examined corresponding information, including diagnoses, imaging and test results, available via linked electronic health records, to determine whether the patients had heart disease or showed signs of declined cardiac function.
The researchers found that patients with cardiomyopathy who have the mutations fare worse, even on treatment, than patients with the condition who don’t have a mutation. The finding, researchers say, underscores the value of ordering a genetic test for patients who have been diagnosed with cardiomyopathy. That said, Arany cautions against patients who don’t have heart disease undergoing genetic tests for titin variants.
“It’s clear that these gene mutations have a real effect on one’s heart, and yet, there are a lot of people carrying the deleterious mutations right now who are fine.” … “While our study moves us one step closer to being able to predict, based on one’s genes, who will get this disease, there is still a difference between these two populations that we don’t yet understand. The next step will be to identify the specific variable causing some of these patients to get heart disease.”
“For now, I would not recommend people get genetic testing for the titin variants because that will just make them anxious for something that’s highly unlikely.” … “That may change, for example, if we were to find that the combination of a TTN gene mutation and a mutation in another gene causes people to get the disease, then we’d recommend genetic testing for both of the variants. But right now we still don’t know enough.” – Zoltan Arany, MD, PhD, corresponding author, professor of Cardiovascular Medicine, Perelman School of Medicine, University of Pennsylvania.