Jonathan the tortoise retains stable DNA repair controls at an estimated 194
Researchers identified 287 unique gene variants and unusually stable gene regulation in the tortoise, with the aim of informing human treatments.
Jonathan, a giant tortoise estimated to be 194 years old, has retained remarkably stable genetic regulation linked to DNA repair and energy production, according to researchers investigating his exceptional lifespan.
The study identified 287 unique gene variants that the researchers say help limit the effects of ageing. Their findings suggest that Jonathan’s longevity reflects not only his genes, but also how little the mechanisms controlling their activity appear to have changed.
Believed to be the world’s oldest living land animal, Jonathan is an Aldabra giant tortoise thought to have hatched in 1832, five years before Queen Victoria came to the throne. He was a contemporary of Charles Darwin and Charles Dickens.
He has spent most of his life in the grounds of Plantation House, the governor’s residence on St Helena, a British Overseas Territory in the South Atlantic. Already fully grown, he arrived from the Seychelles 144 years ago as a gift to the governor.
The research, published in Science Advances and led by the longevity research non-profit organisation Kallel, examined both his genetic make-up and his epigenome: the switches that control gene activity. It marks the first investigation of a giant tortoise’s epigenome.
The 287 variants identified are associated with processes including DNA damage repair, inflammation reduction, insulin regulation and cancer suppression, the researchers explained.
They also compared Jonathan’s epigenome with those of younger giant tortoises of the same species. The switches controlling DNA repair and metabolism were very similar, suggesting unusual stability in systems that normally change with age and contribute to declining bodily function.
Dr Justin Gerlach, a Cambridge University scientist involved in the study, said: “We found that the gene regulators involved in energy production and DNA repair have remained incredibly stable in Jonathan over almost two centuries.
“There are few creatures that could tell us more about ageing than the giant tortoises of the Galapagos and Seychelles islands.”
Those tortoises are the last survivors of animals that once dominated the ecology of many of the world’s islands. Dr Gerlach has studied their ecology and conservation for several decades, but this is his first paper analysing their exceptionally long lives.
He added: “Working with a really old giant tortoise is such a privilege: you get a sense of the tortoise being your collaborator, not your study subject.”
For Kallel, the ambition is to turn insights from such longevity into treatments for people. The findings concern Jonathan’s biology; their application to human ageing remains a goal rather than an established outcome.
The study’s senior author, Dr Stephen Clark, Kallel’s founder, said: “Nature has already solved the puzzle of ageing in remarkable ways, and Jonathan’s genome provides a blueprint for cellular resilience.”
He added: “Our goal is to take these evolutionary insights and immediately translate them into practical, affordable treatments for everyday people.
“Ageing is the greatest risk factor for nearly every chronic disease we face, and through the generosity of philanthropic partners, we can democratise access to longevity medicine.”