About 5% of whales die of cancer. On the other hand, the rate of death from cancer in humans is 11-25%. Why does this difference occur?
Scientists are working on the ‘Saengeo Zoo’ project to unlock the secret. Alex Kagan, head of the Wellcome Sanger Institute in the UK, who is leading the project, revealed the results of an analysis focusing on mammals on the 8th (local time). The analysis of animals that died naturally at Animal London included most mammals, including lions, tigers, giraffes and ferrets.
The analysis showed that shorter-lived species are more likely to develop cancer-causing cell mutations more rapidly. It was found that long-lived species accumulated mutagenesis at a slower rate, while short-lived species accumulated mutagenesis at a faster rate.
For example, humans develop 47 mutations per year, whereas mice develop about 800 mutations per year. The average lifespan of a rat is about 4 years, and the average lifespan of a human is 83.6 years. In the case of bowhead whales, which have an average lifespan of 100 to 200 years, it is analyzed that mutations occur more slowly.
The number of mutations that occur in different animals over a lifetime is similar. The research team said, “All mammals studied showed that they accumulated about 3,200 mutations during their entire lifespan. It is surprising that similar numbers of mutations occur at the end of lifespan.”
Scientists have been studying the low incidence of cancer in whales. It was found that whales, more than other animals, reduce the incidence of cancer by allowing cells to die immediately even if their DNA is slightly damaged, or that whales divide cells slowly, giving them enough time to correct damaged parts. These are studies that can be used for human cancer conquering strategies.
Researcher Kagan’s team plans to expand the analysis target to plants, insects, and reptiles. “If you look at the case of ants, worker ants and queens have the same genes, but queens live 30 years and worker ants 1-2 years,” Kagan said. “This suggests that the queen ant has a better DNA repair function.” revealed
The research team also pointed out that lab mice may not be suitable for cancer research. “Mice have a very short lifespan, so they may not be the best models for cancer research,” Kagan said. “You should consider studying animals with longer lifespans.”