Are elephants zombies walking among us?
A recent study found that elephants are more resistant to cancer than we are as humans. Clues pinpoint to a ‘zombie gene’.
Elephants—big and beautiful creatures
I have always been a huge fan of elephants. As a kid, I used to watch all the Disney movies with elephants, like the Jungle Book and Tarzan, and go to the zoo and admire them. I even have an elephant tea mug at home.
The big, bad cancer—rates of occurrence in elephants
There is a lot of research being done relating to cancer. It affects so many people in society; I had a family friend a few years ago that died of lung cancer and had never smoked in his entire life.
Logically, bigger animals should have higher cancer rates. Because they are bigger, they have more cells in their body, which should make them prone to more cancer mutations. So it makes sense why there are a lot of people suffering from cancer.
This doesn’t just apply to people. For example, bigger dog breeds have higher cancer rates than smaller dog breeds.
But, this is not the case for elephants. A study looked at the relationship of cancer prevalence in different animals and found that while humans have a cancer occurrence of 11-25%, elephants have a cancer rate of 4.81%. That’s almost 10% lower than humans.
This fact peaked my fascination for elephants further. I thought it was so interesting that they don’t get cancer as much as humans, given how big they are. I wanted to find out how this is possible.
How are elephants less vulnerable?
Humans have a gene, called p53, which helps to suppress or stop tumors from forming. We have 2 copies of it whereas elephants have 40.
On top of that, a study using African elephant cells found that elephants have a ‘zombie gene’ to help cancer resistance. When I say zombie, I don’t mean they are going to start eating brains. Instead, when the gene is activated, it will kill other cells.
So while elephants have 40 copies of p53, they also have 7-11 copies of a LIF gene, which stands for leukemia inhibitory factor. One of these, LIF6, has only been found in elephants, and it serves a purpose in cancer resistance.
P53 activates LIF6 to kill cells with DNA damage. LIF6 is acting as a zombie gene to get rid of cells that could cause cancer later down the track.
What does this mean for us?
In Australia, it was estimated that there were 138,000 cancer diagnoses in 2018 alone. This number was even higher in the United States, with 1,735,350 people being diagnosed in 2018. So cancer affects a lot of people.
But it isn’t all bad. Scientists are trying to determine if there are other ways that elephants have less cancer incidences besides having more tumor suppressor genes and LIF6, which could help develop cancer treatments in the future.
For more reading on how these gentle giants are helping to fight cancer, here is a link: https://www.nationalgeographic.com/science/2018/08/news-cancer-elephants-genes-dna-new-research/