The secret tool whales use to avoid cancer for over 200 years
Why do some animals live for a few days, while others live for centuries? A clue could be found in understanding how longer-living species avoid age-related diseases. Boasting a 200 year life span, the bowhead whale is the longest living mammal, expertly evading one of the deadliest age-related diseases: cancer. Cancer is a disease originating from mutations and breaks in the genetic material of our bodies, DNA. Mutations accumulate over time as we age, and if they occur in the right places, they can cause tumors and eventually, death. So how do the bowhead whales stop it?
Nature has figured out a few different strategies to avoid cancer. For example, human cells resist cancer by requiring a cell to get multiple mutations, sometimes needing five or more before disease occurs. Scientists found that cells from bowhead whales actually require fewer mutations than human cells to become cancerous, making them more vulnerable in this respect. However, another strategy is to avoid mutations altogether, or even repair them in real time. In comparison to both mice and humans, cells from bowhead whales have less frequent mutations, and were also found to be incredibly good at repairing a particularly damaging type of mutation: double stranded DNA breaks. Scientists think that this may be due to a particular protein these whales have in abundance called CIBRP. This protein can help repair broken DNA and is activated by cold temperatures – like the water these whales call home. This heightened ability to repair mutations as they occur may underlie how these whales prevent cancer for centuries.
Bowhead whales avoid cancer and its early death by using a very different approach than that of humans. Instead of weathering the storm of many mutations, these whales are much better at repairing the damage at the source. By looking at a wide range of species, we can understand many unique ways animals fight to survive to old age.
This study was led by Denis Firsanov, PhD, a Research Associate at the University of Rochester and Max Zacher, a PhD candidate at the University of Rochester
Managing Correspondent: Sophia Renauld
Press Article: This whale lives for centuries: its secret could help extend human lifespan, Nature
Original Research Article: Evidence for improved DNA repair in long-lived bowhead whale, Nature