South or North Indians? Bengaluru research reveals which group is more at risk of heart diseases

A new study conducted in Bengaluru has revealed that South Indians carry harmful genetic mutations that increase the risk of Hypertrophic Cardiomyopathy.

A new study by researchers at the Institute for Stem Cell Science and Regenerative Medicine (inStem) in Bengaluru has uncovered a distinct genetic pattern among people of South Indian origin that significantly raises their risk of developing hypertrophic cardiomyopathy (HCM). Published in the Journal of the American Heart Association, the research reveals previously overlooked genetic mutations that differ markedly from Western populations - a finding that not only reshapes current understanding of HCM in India but also emphasises the urgent need for population-specific screening and more inclusive cardiovascular research.

What is hypertrophic cardiomyopathy?

According to the Journal of American Heart Association, “Hypertrophic cardiomyopathy (HCM) is a diverse genetic heart condition that affects one in 200 to 500 people globally. It is defined as thickening of the left ventricle without other cardiac or systemic metabolic disorders.” The AHA states that most HCM cases arise from mutations in genes responsible for producing sarcomere proteins - the structures that enable the heart muscle to contract. These genetic mutations have become crucial for achieving accurate clinical diagnosis. In addition, around five percent to 10 percent of HCM cases are linked to genes outside the sarcomere pathway. Among all confirmed genetic causes, variants in the MYH7 and MYBPC3 genes account for the majority of diagnosed cases.

Research subjects

Researchers from the Institute for Stem Cell Science and Regenerative Medicine (inStem) discovered that people of South Indian origin carry harmful genetic mutations that increase the risk of developing Hypertrophic Cardiomyopathy - a serious condition that can lead to heart failure or sudden cardiac death. The study, conducted in Bengaluru, analysed gene sequences from a large cohort of South Indian HCM patients with mixed cardiomyopathies - including primary HCM, secondary hypertrophy, other types of hypertrophy, and dilated cardiomyopathy.

Researchers initially recruited 1,558 unrelated South Indian patients, and eventually performed detailed genetic analysis on 335 primary HCM patients. The patient pool was assembled in collaboration with leading cardiology centres - Madurai Medical College and Government Rajaji Hospital in Madurai, Government Medical College in Kozhikode, Sri Jayadeva Institute of Cardiovascular Sciences and Research in Bengaluru, and Amrita Institute of Medical Sciences and Research Center in Kochi.

What did the study find?

The research team identified thousands of harmful genetic mutations, revealing that South Indian patients exhibited fewer mutations in the two most commonly affected genes worldwide - MYBPC3 and MYH7. Instead, they showed greater variation in genes such as MYH6, which have traditionally received less attention in global cardiology research. This suggests a shift in the genetic profile that was typically seen in European and American HCM patients. This distinctive pattern challenges long-standing assumptions about HCM genetics and highlights the need for cardiovascular research tailored to India’s diverse populations.

What does this imply?

The findings have far-reaching implications for the future of cardiac care in India. By understanding these unique mutations, doctors can more accurately diagnose individuals at risk of sudden cardiac events and strengthen preventive screening programmes - particularly for young adults who often show no early symptoms.

A report in the Deccan Herald states that Dr Perundurai S. Dhandapany, Associate Professor at BRIC-inStem and corresponding author of the study, said, “It (the research) opens the door to study other genetic conditions where Indians have unique genetic signatures and enables a better, inclusive screening programme for sudden cardiac deaths.”

The study is expected to be a game-changer for personalised medicine in India. With the identification of population-specific genetic markers, doctors can now work towards developing targeted diagnostic tools and tailored treatments, improving early detection and long-term clinical outcomes for South Indian patients.

Note to readers: This article is for informational purposes only and not a substitute for professional medical advice. Always seek the advice of your doctor with any questions about a medical condition.