Bowhead whales, known to live for over 200 years, have shown an exceptional ability to repair damaged DNA, a trait that could explain their longevity and resistance to cancer. These marine mammals, found near the northern tip of Alaska, have intrigued scientists with their impressive lifespan and large body size.
The bowhead whale, Balaena mysticetus, can grow up to 18 meters long and weigh over 80,000 kilograms. Despite the vast number of cells in their bodies, which increases the chance of dangerous mutations during cell division, these whales exhibit a remarkable resistance to cancer. This phenomenon, known as Peto’s paradox, suggests that these large-bodied animals have robust cancer defenses.
Previous research has shown that elephants, another large and long-lived species, have extra copies of a tumor-blocking gene called TP53. This gene helps elephants manage DNA damage by eliminating affected cells. However, bowhead whales seem to employ a different strategy. Instead of preventing damage, they repair it.
In a study conducted by Vera Gorbunova at the University of Rochester, New York, cells from bowhead whale tissue were found to be efficient and accurate at repairing double-strand breaks in DNA. These breaks sever both strands of the DNA double helix, and the whale cells were able to restore the broken DNA to a near-original state more often than cells from other mammals. The study also identified two proteins, CIRBP and RPA2, in bowhead whale cells that are part of the DNA repair process.
Understanding how different animals resist cancer could potentially lead to effective treatments for humans with cancer. Although such applications may be far in the future, these findings highlight the importance of studying animals with low cancer rates. The study of animals with large bodies and long lifespans could hold the key to cancer medicine.
This article was adapted from the original by Meghan Rosen on Science News.