A DNA study of the giant tortoise Jonathan, published in Science Advances, identifies unusually ordered regulation around genes involved in mitochondrial function. The observational comparison offers possible clues to the animal’s extreme longevity. It has not established why Jonathan lived so long or demonstrated a treatment for humans; further validation with blood samples is needed.
Jonathan, a giant tortoise living on Saint Helena in the South Atlantic, is the subject of a DNA study published in Science Advances on 7 October. Researchers found low disorder in regulatory regions associated with mitochondrial function. Mitochondria supply cells with energy. The observational comparison suggests a possible contribution to Jonathan’s longevity, with its causal role in his long life still unestablished.[1], [2]
The research began with a request for a blood sample in 2017. Concern about Jonathan’s health prevented that collection, but veterinarian Joe Hollins was allowed to take a small tissue sample from inside his cheek. An international collaboration led by Stephen Clark and genomics specialists assembled the animal’s genome and examined DNA methylation, chemical marks involved in regulating gene activity.[1]
The earlier author preprint was published before peer review on 6 February 2025. It presents the genome and methylation comparison underlying the reported work. The proposed explanation concerns regulation associated with mitochondrial energy production; it offers no treatment shown to extend human life. Findings from this individual animal require further testing before being applied more broadly.[1]
Clark says additional studies using blood samples are needed to validate the finding. His team also plans investigations in other long-lived species and other pathways associated with aging. Jonathan was hatched in about 1832 in the Seychelles and brought to Saint Helena in 1882. He lives on the grounds of Plantation House, the island governor’s official residence.[1]
