Elephants don't get cancer, a disease that has taken millions of human lives and largely remains an enigma for modern scientists and health experts.
Why? Well, a new study claims elephants have special genes that is able to fix mutated DNA. Humans have them, yes, but in slightly different variants.
The study, published in the Cell Reports journal on March 6 could help humans understand cancer better and, ultimately, fight better ways of fighting it.
DNA Mutations
University of Utah researchers studied animal traits that shed light on the genetic makeup of humans. For example, the DNA that lends bats their pointy ears, when mutated, can cause an ear deformity called Stahl ear. Another one is a DNA that causes fingers to be fused together, which is abnormal to humans but helpful for bat wings.
They weren't looking for anything in particular in their research, according to geneticist Christopher Gregg.
"We were working on the elephant as a positive control in our study and we discovered parts of the genome that were important for nose development," he said.
Then he had a conversation with pediatric oncologist and colleague Josh Schiffman, who advised him to take the study in a different direction. Schiffman actually had been studying why elephants don't get cancer.
Elephants And Cancer
Biologists have been trying to answer this question for years, and they haven't had a clue. Even more odd is the fact that elephants are large — and cancer is linked to extreme body growth. Elephants, one of the largest species in the world, somehow don't get them. How could that be?
In 2015, Schiffman discovered that elephants have 20 copies of a gene called p53, the activity of which stops the formation of tumors, the bedrock of cancer. It is known to fix damaged DNA, and broken DNA can lead to cancer. Humans only have one p53 gene.
Gregg and his colleagues then attempted to find out if there were any more unique DNA makeup that renders elephants unable to get cancer. They found one. Its name is the Fanconi anemia pathway, and all mammals, including humans, have it.
"People with mutations in [Fanconi anemia pathway] have very high rates of cancer," said Gregg.
"This is a master regulator of DNA repair."
Blasting them with radiation, the researchers found that elephants' immune cells quickly repair damaged DNA, which is a crucial process in avoiding cancer. More intricately observing these genes in humans may uncover new ways to combat cancer or perhaps develop ingenious methods of cancer resistance.
