HYDERABAD, India—Researchers from India, the United Kingdom and the United States have discovered that a particular mutant gene increases the risk of cardiomyopathy in South Asians by as much as sevenfold, putting one percent of the world's population at much greater risk of heart failure.
The scientists' findings, published in the article A common MYBPC3 (cardiac myosin binding protein C) variant associated with cardiomyopathies in South Asia in the journal Nature Genetics in January, indicate 4 percent of people of South Asian descent carry this MYBPC3 mutation.
"The mutation leads to the formation of an abnormal protein," says one of the researchers, Kumarasamy Thangaraj of the Centre for Cellular and Molecular Biology in Hyderabad. "Young people can degrade the abnormal protein and remain healthy, but as they get older it builds up and eventually results in the symptoms that we see."
The study, which found this mutation almost exclusively in people originating from India, Pakistan, Sri Lanka, Indonesia and Malaysia, may explain a medical mystery that has stymied health experts for some time: why South Asia accounts for a disproportionately large share of the world's cardiovascular disease cases. Around 30 percent of global deaths each year are due to heart disease and other cardiovascular problems, and the World Health Organization estimates that by 2010, India alone will account 60 percent of the world's heart patients.
What is less clear, however, is how much this discovery will help in the near term. Certainly, one route of commercialization that could come out of this research would be screening tests to identify carriers of the gene in the womb or at an relatively young age.
But as noted by Chris Tyler-Smith, a senior investigator at The Wellcome Trust Sanger Institute in the United Kingdom and one of the study's researchers, healthcare professionals would only be able to offer to such people the same advice they offer generally to people to avoid heart disease: have a healthy diet, exercise and avoid smoking. In a commentary about the study, Britain's National Health Service said the very same thing.
Also, as Peter Weissberg, medical director at the British Heart Foundation, notes, "There is no evidence yet that early detection will lead to improved outcome since we have no idea if the outlook for this group can be modified by conventional heart failure treatments."
But Tyler-Smith sees commercial opportunities in the future for therapies as more understanding of the mutation and its effect come to light.
"In the longer term, I think trying to improve the efficiency of the protein degradation mechanism might be a novel approach for treatment," he says. "All you would have to do is postpone the effects for a few decades." DDN
