Researchers studying Jonathan, a giant tortoise believed to be about 194 years old, uncovered a potential clue to his remarkable longevity.
The study found that genes involved in cellular energy production showed unusually low levels of a type of genetic disorder associated with aging.
The findings could help scientists explore ways to protect human health as we age, but more research is needed before they can be applied to people.
What if understanding how some animals live for nearly two centuries could help scientists figure out how humans might stay healthier as they grow older?
That’s one question researchers are exploring through Jonathan, a giant tortoise widely considered the world’s oldest living land animal.
Jonathan is believed to have hatched around 1832 and has lived on the island of St. Helena since 1882. Despite his extraordinary age, researchers found evidence that some of the genetic processes involved in keeping his cells functioning have remained remarkably well organized.
The study, led by researchers working with Vanderbilt Health, focused on a biological process called entropy. In simple terms, entropy describes how systems become more disordered over time. In the body, this kind of disorder can interfere with normal cellular functions and contribute to aging.
The researchers hope their findings will help scientists better understand how certain biological mechanisms might preserve health later in life.
How researchers studied Jonathan’s genes
The team began investigating Jonathan in 2017, when lead researcher Stephen (Wes) Clark sought permission to collect a blood sample. Because of concerns about the tortoise’s health, that request was denied. Instead, a veterinarian collected a small tissue sample from inside Jonathan’s cheek.
Scientists then analyzed his genome, which contains his DNA, and his epigenome, which includes chemical markers that influence how genes are switched on and off without changing the underlying DNA sequence.
The researchers paid particular attention to DNA methylation, a process involving chemical groups that help regulate gene activity. They examined the patterns of these markers to assess how much disorder had developed in different areas of the genome.
Their analysis revealed that gene-regulating regions associated with mitochondrial function and RNA processing had what scientists call low methylation entropy. Mitochondria are structures inside cells that help produce the energy needed for the body to function.
What the findings could mean for human health
The results suggest that Jonathan may have retained more orderly regulation of genes involved in cellular energy production than scientists might expect in an animal of his age. That organization could help preserve the efficiency of important cellular processes and potentially protect against some age-related decline.
For consumers, however, the findings are an early scientific clue, not a new anti-aging treatment. The study does not establish that people can reproduce Jonathan’s biology or that any particular supplement, medication, or lifestyle change will extend human life.
The researchers also emphasized the need for additional studies to validate their findings. Future work could include analyzing blood samples, which may provide a more complete picture of DNA, and investigating other long-lived species and biological pathways involved in aging.
Ultimately, Jonathan’s unusual biology could give scientists a new direction for studying healthspan — the period of life spent in good health. Understanding why some organisms maintain cellular function for so long may eventually help researchers identify ways to support healthier aging in humans.