‘Zombie Gene’ Could Be Why so Few Elephants Die of Cancer
Elephants are bringing a genetic gun to a cancer knife-fight.
By Neel V. Patel
The longer you live, the higher your chances of developing cancer creep toward 100 percent. Moreover, the larger you are, the greater your chances are of developing cancer as well — more cells in your body mean there are more opportunities for mutations to strike and encourage a tumor to grow. This holds true when comparing individuals within a species (including humans), but the trend falls apart when researchers compare cancer rates between different species — a mystery we call Peto’s Paradox. Elephants are some of the biggest mammals who roam the Earth, so mathematically they should be hounded by cancer at 100 times the rate of humans. Yet death by cancer among these eight-ton animals hovers around five percent, compared to 11 to 25 percent of humans. What gives? Is it metabolic rates? Tumors that are able to parasitize other tumors? Certain genes?
Unsurprisingly, the answer comes down to genes. We’ve known for decades now that the gene that codes for a protein called p53 is a critical tumor suppressor. The protein directs the body’s response against damaged DNA and prevents these cells — whose mutations could otherwise confer an ability to proliferate uncontrollably — from…
