Transmissible cancer is a time capsule from the earliest dogs

These Alaskan malamutes share a common ancestor with an 11,000 year old tumor.

Innumerable cases of cancer arise each year throughout the animal kingdom. As far as we’re aware, that cancer has only twice outlived the animal in which it originated by spreading to new hosts. One of these forms of cancer strikes the Tasmanian Devil and appears to have evolved within the last few hundred years. The second circulates among dogs, and its origin has been harder to pin down.

Now, researchers have sequenced the genomes of two cases that originated in Australia and Brazil and have shown that the cancer contains a mixture of markers. Some of them are from wolves and some are from domestic dogs, suggesting the cancer originated very close to the origin of dogs as a distinct population. Once established, the cancer circulated among a limited population of dogs for over 10,000 years before going global about 400 years ago.

We’ve actually known about the cancer since 1810, when the first report of it was published in London. It tends to be a sexually transmitted disease, causing large growths in the mouth or genital tract before the immune system gets it under control. Once controlled, the growths vanish and the dog remains immune for the rest of its life.

Read 9 remaining paragraphs | Comments

via Ars Technica http://ift.tt/1mSdrKQ

Advertisements

Leave a Reply

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

WordPress.com Logo

You are commenting using your WordPress.com 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 )

Google+ photo

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

Connecting to %s