alt Hacker NewsAren't the elephants and whales orders of magnitude better than us at that though (they have roughly as many cancer as we do, but with respectively x100 and x1000 times as many cells.
Or is it the second layer that works better for them?
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also, Elephants have a much higher copy number of a gene called p53/ It codes a protein that acts to force suicide in cells that have damaged DNA (think from UV light, cigarette smoke, age, etc). In cancer this is a common 'early' mutation that allows collection of further mutation and progession towards cancer. In having many more copies of p53, it makes it less likely the p53 function will be eliminated
I am not sure how much consensus there is around it but this is so cool I have to repeat it sorry: Whales and elephants do develop cancers but since those cancers also have mutations, well their cancers have cancers and overall the cancers are never able to grow big enough to threaten the whole organism.
Too big to fail basically
Different species do have different levels of protection, and different lineages tend to employ different methods of protection. For example elephants have numerous duplicates of cancer suppression genes, whereas naked mole rats produce a variant of hyaluronan which prevents tumor formation. When compared to other great apes, Humans seem to be worse at both layers of defense.
It's worth noting though that humans also have much higher levels of exposure to many carcinogens than most animals, and we screen for cancers at a much greater rate for humans, so just because a species has lower cancer rates doesn't necessarily mean their cancer defenses are better.