Ridiculously fast, uniquely fast, actually, among mammals, they're the only body parts that can regenerate completely.

And they do re growing year after year from just a small stones.

So you'd think, with all those cells whose job is to divide really fast that animals in the dear family would get cancer more often than others.

But do you actually get cancer less way less like 1/5 as often as other mammals?

At least based on statistics from animals in captivity in a massive 2019 genome, study might have revealed why, in a paper published in the journal Science, researchers analyze the genomes of certain species of deer along with dozens of related species, and the genetic changes they found in the deer DNA go a long way towards explaining both how antlers grow so fast and how that growth doesn't lead to cancer.

More off usually sells growing, and dividing too fast is a problem.

When cell growth escapes the body's control, those cells conform.

A tumor cancer is what happens when those uncontrolled cells become malignant, capable of escaping to other parts of the body and causing extra cell division There, too, with their super fast growth antlers bear some resemblance to tumors.

In fact, the 2019 study found that in terms of what genes they express, antler cells are more like bone cancer than regular bone.

That includes genetic changes that promotes cell growth and division.

And based on what we know from studies and other species, similar changes can often cause cancer if left unchecked.

For example, Antler sells express a lot of a gene called fost, meaning they contain more of that gene's protein product than you'd normally expect.

And Fosse instruct cells to grow and divide more.

That should be a big risk cancer wise.

Usually it takes a bunch of problematic genes working together to cause cancer.

But in mouse studies over expressing just this, one gene is enough to cause bone cancer.

Any cancer biologist will tell you that Foss is really, really me and dear strongly expressed false and a bunch of other genes that can lead to cancer.

But it turns out dear also have genetic changes to keep all that extra cell division from turning into cancer, mainly involving P 53 sometimes known as the master tumor suppressor, P 53 makes a protein that checks sells for DNA damage.

If the damage is flexible, the P 53 protein tells the cell to repair it.

If it's not fixable, it makes the cell self destruct.

Elephants, which also have very low cancer rates, have extra copies of the P 53 gene in their DNA.

Researchers think that's a big part of what makes them less prone to cancer.

Dear don't have extra copies.

Instead, they've evolved more genes to support what P 53 does and help it along.

They've also evolved a bunch of other tumor suppressor genes specifically expressed in their antlers.

The researchers suggest that these two sets of genetic changes might have evolved together.

Growing antlers helped attract mates, which was good because babies.

But it also involved genetic changes that led to superfast cell division, which was bad because cancer.

In the end they evolved.