Contagious dog cancer analysed
Kat - One other thing that's interesting and exciting, but also actually quite icky is the story that's coming out this month about this contagious dog genital cancer. And this was a research from Elizabeth Murchison at the Wellcome Trust Sanger Institute and published in Science.
She's well-known for working on the other known transmissible contagious cancer, which is Tasmanian devil facial tumour, which the devils transfer by biting each other. And now, this is a dog genital cancer that can also be transferred. What has she discovered about this?
Nell - Oh, yes, it's kind of horribly fascinating, you know, you get a headline like "11,000-year-old genital cancer" and you can't help but read on.
Kat - Eww!
Nell - So what they're looking at is it's a tumour. It's a transmissible tumour, so it arose in one dog - we think about 11,000 years ago - and it's been going ever since, which is amazing and a really interesting example of what can happen as cancers evolve. And the researchers have looked at all the genetic mutations within it. It has about 2 million, which is a huge number compared to a lot of human cancers, which might have around a 1,000, maybe up to 5,000 mutations.
So, I guess, the really interesting question is how on earth does it survive with all of these mutations, causing it to go wrong in all kinds of interesting ways? And they've actually have been able to look back and figure out what type of dog it arose in. And then I think it was something like an Alaskan malamute or a husky maybe, with a short straight coat - grey, brown, maybe black colouring. They can't tell if it was a male or female though, from what they've got at the moment.
Kat - It is really, really fascinating stuff. A real bit of genetic archaeology. And they are proposing that the genetic variations that they're seeing in the tumours from around the world suggests that it started to spread globally about 500 years ago, during the dawn of the age of exploration. So all these sailors are off conquering the New World, taking these dogs with genital tumours with them. It's not a very nice idea.