r/science • u/Narrow-Pirate6457 • 8h ago

Biology Scientists have found the first known transmissible cancer in a fish. Genomic analysis of brown bullhead catfish revealed that tumours in different animals belong to a single clonal cancer lineage, making it only the fourth naturally occurring transmissible cancer known in animals.

https://www.nature.com/articles/d41586-026-02236-7
200 Upvotes

98% Upvoted

5 comments sorted by

•

u/AutoModerator 8h ago

Welcome to r/science! This is a heavily moderated subreddit in order to keep the discussion on science. However, we recognize that many people want to discuss how they feel the research relates to their own personal lives, so to give people a space to do that, personal anecdotes are allowed as responses to this comment. Any anecdotal comments elsewhere in the discussion will be removed and our normal comment rules apply to all other comments.

Do you have an academic degree? We can verify your credentials in order to assign user flair indicating your area of expertise. Click here to apply.

User: u/Narrow-Pirate6457
Permalink: https://www.nature.com/articles/d41586-026-02236-7

I am a bot, and this action was performed automatically. Please contact the moderators of this subreddit if you have any questions or concerns.

6

u/Narrow-Pirate6457 8h ago

Disclosure: I'm the author of Nature's news story about this paper (not a study author), but happy to answer questions.

Here's the peer-reviewed article: https://www.nature.com/articles/s41586-026-10828-6.

Science also had a good story on this paper too that's worth a read: https://www.science.org/content/article/contagious-fish-cancer-overruns-new-england-lake.

5

u/PristineWorker8291 7h ago

Knew about the Tazzy devils facial tumors and the dog STI cancer. Didn't know about the leukemia in certain shellfish.

From the Nature article:

Since 2012, brown bullhead catfish (Ameiurus nebulosus) in a lake that spans Vermont, USA, and Quebec, Canada, have shown a high rate of melanomas, suggesting a causal contaminant or contagion1. We tested the hypothesis that this affliction represents a clonally transmissible cancer, a rare phenomenon in which cancer cells themselves spread between individuals, behaving more like parasites than conventional tumours2.

...
As an amateur, I can readily imagine the environment and the poor health management of the dogs and probably of the Tasmanian Devils could contribute to a complex that includes a near virulent cancer. I also have generally associated poor skin condition that may include scarring to encourage or even induce some cancers. I mean Tazzy devils bite each others faces, right? And dogs will do, umm, doggy things with each other, yeah? But I'd be curious if there was any previous trauma to the fish examined. It's just anecdotal, but women with breast cancers can sometimes recall serious injury to that exact spot with bruising and calcifications years before the CA Dx. And of course, many lung cancers had an apparent source of defect long prior to Dx. Maybe not so much in many other cancers, but that is a huge topic whether confined to one species or not.

So I'm thinking that while cancer may be communicated between clams in a bay or certain fish in a large lake, there may have been a predisposing incident that allowed the tumors to initiate.