Jonathan’s genes may hold clues to his extraordinary longevity

At 194 years old, Jonathan, a giant Aldabra tortoise living on the remote island of Saint Helena in the South Atlantic, is officially the world’s oldest known living land animal. Scientists have now analyzed his genome and epigenome in an effort to understand how he has avoided many of the biological effects of aging.

Researchers from the Kallal Foundation and Vanderbilt Health found that genes involved in mitochondrial energy production in Jonathan have retained remarkably youthful patterns. Mitochondria are the structures responsible for producing energy in most animal cells, and their dysfunction is considered one of the hallmarks of aging.

The study focused on epigenetic changes, particularly DNA methylation patterns. These patterns tend to become increasingly disordered with age, a process sometimes described as an increase in methylation entropy. However, the researchers found that the promoters of Jonathan’s mitochondrial genes showed very little of this age-related disorder.

Remarkably, Jonathan’s pattern was similar to that observed in a five-year-old tortoise and significantly different from patterns found in 91-year-old specimens. Researchers say this may help explain how the tortoise has maintained cellular functions despite his extraordinary age.

The findings, published in Science Advances, suggest that protecting mitochondria from age-related changes in gene regulation could potentially contribute to healthier longevity. However, the research does not establish that the same mechanism can be used to extend human lifespan.