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3 clusters · 23 sources · 7 days · First seen 9 days ago · Last updated 3 days ago

Categories: HEALTH

Transmissible melanoma in Lake Memphremagog catfish

Entities: Lake Memphremagog · University of Vermont · Nature (journal) · Julie Dragon · Brown bullhead catfish (Ameiurus nebulosus)

Overview

Researchers have confirmed a fourth transmissible cancer, the first in a freshwater species, affecting brown bullhead catfish in Lake Memphremagog (Vermont–Quebec). Anglers first noted dark, tar‑like lesions in 2012; surveys from 2014 to 2017 found roughly one‑third of sampled fish carried the melanoma. Whole‑genome sequencing showed tumor cells from different individuals share a common lineage, indicating direct cell‑to‑cell transmission. The study, led by Julie Dragon of the University of Vermont and co‑authored by Peter Emerson of the Vermont Fish & Wildlife Department, was published in *Nature* on 22 July 2026, with a follow‑up on 25 July reaffirming the findings and noting no evidence of human infection. Consumption of affected fish is discouraged. Ongoing work is probing the cancer’s origin and pathways of spread, and officials warn that its prevalence in this key indicator species could signal broader environmental and water‑quality concerns. The discovery expands the list of transmissible cancers to four worldwide and offers a novel model for studying metastatic mechanisms relevant to human oncology.

Claims

What the coverage asserts, and how well corroborated each claim is across sources.

[● 10 SOURCES] Researchers identified a transmissible cancer in brown bullhead catfish (Ameiurus nebulosus). (multiple articles)
[● 10 SOURCES] The cancer is a melanoma that spreads via living tumor cells moving directly between fish. (multiple articles)
[● 10 SOURCES] The first lesions were observed in 2012 in Lake Memphremagog on the US‑Canada border. (multiple articles)
[● 10 SOURCES] Genetic analysis showed tumor cells from different fish are more closely related to each other than to their hosts, indicating a single transmissible lineage. (multiple articles)
[● 10 SOURCES] There is no evidence that the transmissible cancer can infect humans. (multiple articles)
[● 10 SOURCES] Approximately one‑third of brown bullhead catfish in the studied lake are affected by the tumors. (multiple articles)
[● 10 SOURCES] The discovery adds a fourth known transmissible cancer and is the first recorded in a freshwater ecosystem. (multiple articles)
[● 10 SOURCES] The study reporting the transmissible cancer was published in the journal Nature. (multiple articles)

Timeline

3 days ago

[HEALTH] 4 sources
Transmissible melanoma discovered in Vermont’s Lake Memphremagog catfish
Researchers found a rare transmissible melanoma in brown bullhead catfish from Lake Memphremagog, the first such cancer in a freshwater species, affecting up to a third of fish since 2012.
6 days ago

[HEALTH] 10 sources
Transmissible Cancer Found in Brown Bullhead Catfish in Lake Memphremagog
A melanoma transmissible cancer has been discovered in brown bullhead catfish in Lake Memphremagog (US‑Canada). About one‑third of the fish are affected; tumor cells are genetically identical, and no human risk
9 days ago

[HEALTH] 9 sources
Transmissible melanoma discovered in brown bullhead catfish of Lake Memphremagog
Scientists have identified a transmissible melanoma in brown bullhead catfish in Lake Memphremagog (US‑Canada), the first such cancer in freshwater fish, affecting about 30% of the population and posing noknown

Sources

7dvt.com · ca.news.yahoo.com · diariocorreo.pe · dnyuz.com · donanimhaber.com · ecoticias.com · exame.com · gazetedamga.com.tr · independent.co.uk · kpbs.org · ksfr.org · laverdadnoticias.com · livenowfox.com · master.com.cy · memesita.com · NPR.org · revistaforum.com.br · rionoticias.co · smartsme.com · techno-science.net · thecooldown.com · time.news · world-today-journal.com

This summary has been updated 6 times: see revision history