RIP Taz
An article in the New York Times this week described a disease threatening to destroy the tasmanian devil population that appears to actually be the second known case of a transmissible cancer. This is bad news for the tasmanian devils, of course–it appears that this disease may wipe them from the wild–but I was intrigued to see the confirmation of a idea that I had been pondering recently: whether or not cancers could act as a transmissible disease.
The only other known example of a cancer like this is in dogs, and genetic studies have shown that the canine one is thousands of years old, so it’s really interesting that this cancer appears to have developed much more recently. On a fundamental level, it’s really remarkable that both the dog and tasmanian devil cancers are able to actually survive and grow when they get transmitted between individual animals.
Given the intensity of the body’s usual response to the presence of outside cells–think of the drugs that organ donation recipients have to take to keep their bodies from killing off the foreign tissue–it’s really intriguing to see that this can actually occur in these (albeit extremely rare) cases.
This is also an exciting opportunity for cancer researchers, in that the tasmanian devil disease is so young. Although normal genetic evolution occurs on the scale of hundreds to thousands of years, cancer cells effectively lift the brakes on mutation rates: biologists will be able to watch to see if this disease develops and changes over just the next decade or two.
Some nasty infectious diseases are believed to adapt to become less deadly over time so they can survive and multiply without quickly killing off their hosts (syphilis is one disease where this is suggested to have occurred), so it will be interesting to see if this cancer can strike this balance before it completely wipes out Taz and his cousins.
Tags: cancer, NYT, tasmanian devils