Elephants almost never get cancer thanks to multiple gene copies

日期:2019-02-28 04:16:12 作者:于拼葫 阅读:

CANCER is no match for elephants – and now we might know why. Big animals like elephants live longer and their cells have to divide more. This means we would expect them to be more susceptible to cancer, but that doesn’t seem to be the case. This is known as Peto’s paradox, and Joshua Schiffman at the University of Utah and his team have confirmed that it is real. Using data on captive elephants worldwide, they found that less than 5 per cent of elephants die of cancer, compared with 11 to 25 per cent of humans. The secret seems to be in their genes. By analysing elephant blood, the researchers found that African elephants have at least 20 versions of the p53 gene. This gene protects against cancer because it detects damage in a cell, and can stop it from dividing or cause it to self-destruct. Humans have only one version of it, inheriting one copy of it from each parent. The many elephant versions of the gene could explain why the team found that elephant cells are twice as likely to self-destruct after dangerous radiation exposure, probably preventing tumour formation (JAMA, doi.org/772). Their findings are supported by a second, independent paper published by a University of Chicago team last week (BioRxiv, doi.org/773). <i>(Image: Michael Nichols/National Geographic Creative)</i> This article appeared in print under the headline “Elephants armed with genes that stop cancer” More on these topics: