Some of India’s oldest people possess genes linked to a low heart rate, strong bone health and robust liver function, researchers have found through the country’s first study probing the genetic makeup of octogenarians and nonagenarians.
The study, which analysed the genomes of Indians aged 85 years or older alongside those of younger people, has identified an array of gene variants, including some associated with irregular heartbeat, anxiety, schizophrenia and short height that appear to contribute to longevity.
“We’re hoping our findings will help health researchers develop new strategies for healthy ageing,” said Anuradha Acharya, the chief executive officer of MapMyGenome, an Indian company that provides genome tests to guide diagnosis, lifestyle modifications and insights into ancestry, who led the study.
Acharya and her colleagues used 133 genome samples from octogenarians and nonagenarians collected from across India in collaboration with the Society for Research Initiatives for Sustainable Technologies and Institutions (SRISTI), an Ahmedabad-based non-government entity. They also used 1,134 samples from people aged 18 years to 49 years from MapMyGenome’s own database for the analysis.
Their study, published on Wednesday in the peer-reviewed scientific journal NPJ Aging, has found that people who possess a gene variant denoted as “rs365990” have a 1.75 times higher chance of surviving into the late 80s.
This variant has been known to be associated with a low-resting heart rate which, the researchers said, contributes to enhanced lifespan through reduced stress on artery cells, reduced stiffening of blood vessels and reduced cardiovascular abnormalities.
Gene variants that increase the risk of irregular heartbeat, liver disorders, anxiety and schizophrenia were less common in the octogenarians and nonagenarians, while gene variants associated with low heart rate, low bone fracture risk and short height were more common.
“Our findings suggest that shorter people are more likely to live longer,” Acharya said. The researchers say this is not surprising because independent studies in the past have suggested that shorter people are more likely to have higher resistance to chronic diseases in middle age.
The findings also support the notion that low anxiety levels contribute to increased lifespan.
Similar studies elsewhere in the world have already identified more than 25 so-called genetic markers associated with exceptional longevity. The earlier studies have shown that multiple genetic variants combine to influence human lifespan — no single gene variant is responsiblefor longevity.
Researchers at the University of Connecticut in the US and the University of Exeter in the UK, through a joint study seven years ago, had identified gene variants linked to heart disease, the body’s response to stress and inflammation among those influencing longevity.
Acharya said the growing evidence for multiple gene variants influencing a long lifespan implies that individuals might be able to compensate for the effects of certain gene variants through either lifestyle modifications or medications.
“But we’ll need larger samples,” she said. The researchers have said future studies with larger samples should also combine genomic information with health and lifestyle information of the participants to explore how lifestyle might influence the effect of the longevity-linked gene variants.
The study’s other coauthors are Sandhya Kiran Pemmasani, R.G. Shaktiraju and V. Suraj from MapMyGenome and Chetan Patel and Anil Gupta from SRISTI.