The Greenland humpback whales are among the largest and longest-lived mammals known, capable of living more than 200 years and reaching more than 80 metric tons. For decades scientists have tried to understand how such a large animal can live so long without developing serious diseases such as cancer, since the enormous number of cells that make up its body would, in theory, increase that risk.
A new international study, published in the journal Nature and released by Springer Nature, may now help explain this enigma.
Resistant Cells and DNA That Repairs Rapidly
The researchers compared Greenland humpback whale cells and human cells in the laboratory, exposing both to stimuli that typically trigger cancer-causing mutations, such as ultraviolet radiation. The results showed that, although whale cells could incur mutations, they exhibited far less genetic damage than human cells and, above all, were able to repair damaged DNA with great speed and efficiency.
“These whales seem to have developed exceptional cellular mechanisms for genetic repair, which may be one of the keys to their extraordinary longevity,” explain the authors, among them Jan Vijg and Vera Gorbunova, specialists in cellular aging.
The Protein That Prolongs Life
The team also identified a protein associated with DNA repair in Greenland humpback whales. When this protein was produced in greater quantity in human cells, they showed an improved ability to repair DNA. In a subsequent step, the same compound was tested in fruit flies, where it extended the insects’ lifespan — an indication that this protein could be at the origin of the whales’ remarkable resistance and longevity.
A Paradox Resolved
The study helps explain the so-called “Peto’s paradox,” the observation that larger, more cell-rich animals, such as whales, do not exhibit a higher incidence of cancer than smaller species. According to the authors, enhanced DNA repair could be the answer.
Still, the researchers emphasize that there are limitations: the experiments were conducted with human fibroblasts — connective tissue cells — and not with epithelial cells, where most cancers originate.
Even with this caveat, the conclusions open new avenues into the biological mechanisms of aging and point to potential paths in research on human longevity and cancer prevention.
“The Greenland humpback whales can teach us a great deal about how cells resist the passage of time and disease,” the authors conclude.
