Genome of 194-year-old tortoise reveals clues to its longevity
Scientists sequenced the genome of Jonathan, a 194-year-old Aldabra giant tortoise living on St Helena. His mitochondrial function resembles that of a 5-year-old tortoise, potentially supplying more energy for DNA repair and slowing ageing. Some genetic changes also resemble those seen in human supercentenarians, suggesting ageing mechanisms may be shared across species.
Jonathan, an Aldabra giant tortoise on St Helena, is estimated at 194 years old, far beyond his species’ roughly 80-year average. Because officials declined blood draws, researchers used saliva and cheek swabs, then supplemented missing sequences with DNA from another Aldabra tortoise.
Comparing his composite genome with four other Aldabra tortoises revealed 287 uniquely altered genes. Forty-one appear functionally important, and twelve also appear in longevity databases for other long-lived animals. His mitochondrial-related DNA looked unusually youthful, comparable to a 5-year-old tortoise.
This research may strengthen interest in comparative ageing biology, potentially informing future studies of human healthspan. Older people and those researching age-related disease could benefit if shared mechanisms are confirmed, though tortoise findings may not translate directly. Conservationists and St Helena may see greater attention to Jonathan and species preservation. Any societal impact would likely emerge slowly through science, not immediate treatments.