translating biophilia into a love of life

A self-propagating, parasitic, cellular mass

with 3 comments

I just finished reading David Quammen’s article in the April 2008 issue of Harper’s, “Contagious cancer: The evolution of a killer”. The gist being: cancer evolves, and is demonstrated as being highly infectious in Tasmanian devils.

Poor devils, their relative physical isolation has created an inbred population whose members are genetically very similar – and vulnerable – to a cancer transmitted during mating known as Devil Facial Tumor Disease (DFTD). Not sexually transmitted in the traditional sense, but rather DFTD is a cancer spread by the habit of mutual face-biting during courtship (and so forth).

In humans, cancer is a very unique affair. My tumors would be derived from my own cells, growing unchecked. Henry’s cancerous tumors would be made of his own cells, as would yours. DFTD tumors found on the devils were all genetically identical to one another and distinct from their host. While not quite a distinct “species”, DFTD is a self-propagating, parasitic, cellular mass. As such, DFTD is undergoing cellular replication, environmental selection and epigenetic expression. DFTD may not be a living organism, but as a genetic conglomeration it is evolving.

As Quammen smoothly knit these concepts together, I bumped along on a shuttle during my commute home from work. The proverbial light bulb went on above my head, and I felt a tightness in my stomach. “What if…”s began bubbling up from parts of my brain I’d long considered dried up. Suddenly ideas and questions came to mind, and – more shockingly – the motivation to learn more.

Now I’m looking into topics integrating genetics, evolution, ecology and disease, and reading about research laboratories at university.


Written by morethangray

March 20, 2008 at 11:28 pm

Posted in thoughts

Tagged with ,

3 Responses

Subscribe to comments with RSS.

  1. Wow… this is both interesting and frightening… great post, well written… but scary!

    Naomi Strange

    March 21, 2008 at 7:28 pm

  2. It’s a new way for me to think of cancer – as a proto-autonomous living tissue. And a completely disrespectful living tissue at that!

    Like a true parasite, DFTD recognizes “self” and “host”. As the devils are so inbred, “host” seems to be synonymous with all devils in the population rather than the progenitor “parent” organism (as does human cancer).

    Human cancer has been transmitted between unrelated people. The known cases are uncommon and result from accidents during infectious tissue handling; a surgeon who cut his hand during a tumor-removal surgery later developed a tumor at the site of the cut. The resultant tumor was genetically identical to the cancer patient he was operating on…


    March 21, 2008 at 8:10 pm

  3. […] adaptation, cancer, co-evolution, devils, evolution, red queen, sciencia, tasmanian devils | The first entry made on anthropometaphors was prompted by learning about the evolution of a contagious facial […]

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s

%d bloggers like this: