https://www.science.org/content/article/transgenic-glowing-fish-invades-brazilian-streams Advertisement * * news * careers * commentary * Journals * Covid-19 Science Science * * * Log in * Become A Member [science] science [sciadv] science advances [sciimmunol] science immunology [scirobotic] science robotics [signaling] science signaling [stm] science translational medicine [spj-cover] science partner journals Quick Search anywhere Enter Search Term[ ] Quick Search in Journals Enter Search Term[ ] Quick Search in Journals Enter Search Term[ ] Quick Search in Journals Enter Search Term[ ] Quick Search in Journals Enter Search Term[ ] Quick Search in Journals Enter Search Term[ ] Quick Search in Journals Enter Search Term[ ] Searching: Anywhere AnywhereScienceScience AdvancesScience ImmunologyScience Robotics Science SignalingScience Translational Medicine Advanced Search Search Trending Terms: * covid-19 * climate * science policy * genome editing * batteries Log In Become A Member Quick Search anywhere Enter Search Term[ ] science.org * Custom publishing * collections * videos * podcasts * blogs * visualizations * prizes and awards * authors & reviewers * librarians * advertisers * about * help * * * * * * AAAS Logo * Terms of Service * Privacy Policy * Accessibility * News Home * All News * ScienceInsider * News Features GET OUR E-ALERTS HomeNewsAll NewsTransgenic glowing fish invades Brazilian streams Back To All News * News * Plants & Animals Transgenic glowing fish invades Brazilian streams Aquarium curiosity appears to be thriving after escape from fish farms and may threaten local biodiversity * 11 Feb 2022 * 6:05 PM * BySofia Moutinho Leopard danio Genetically modified zebrafish (Danio rerio) are sold in fluorescent red, blue, and green.Paulo de Oliveira/Minden Share: * Twitter * Linked In * Facebook * Reddit * Wechat * Email issue cover image Table of contents A version of this story appeared in Science, Vol 375, Issue 6582. Fish genetically engineered to glow blue, green, or red under blacklight have been a big hit among aquarium lovers for years. But the fluorescent pet is not restricted to glass displays anymore. The red- and green-glowing versions, more vivid than normal zebrafish even in natural light, have escaped fish farms in southeastern Brazil and are multiplying in creeks in the Atlantic Forest, a new study shows. It is a rare example of a transgenic animal accidentally becoming established in nature, and a concern for biologists, who worry the exotic fish could threaten the local fauna in one of the most biodiverse spots on the planet. "This is serious," says ecologist Jean Vitule at the Federal University of Parana, Curitiba. Vitule, who was not part of the research, says the ecological impacts are unpredictable. He worries, for example, that the fluorescence-endowing genes from the escapees could end up being introduced in native fish with detrimental effects, perhaps making them more visible to predators. "It's like a shot in the dark," he says. The unwelcome visitors are well known to scientists who have used zebrafish (Danio rerio) for developmental and genetic studies for decades. Native to Southeast Asia, the match-size freshwater fish were engineered to glow for research purposes in the late 1990s by endowing them with genes from fluorescent jellyfish (for blue and green colors) and coral (for red). In the 2000s, companies saw the potential of the neon fish as pets. Trademarked as Glofish, they became the world's first genetically engineered species to be commercially available. Now, they are one of the first to escape and thrive in nature. Early on, environmentalists worried about the possibility, and Glofish sales were banned in some U.S. states such as California and several countries--including Brazil. In 2014, a single Glofish was spotted in canals near ornamental fish farms in the Tampa Bay region of Florida. But it had not multiplied, probably because native predators such as the eastern mosquitofish ( Gambusia holbrooki) and the largemouth bass (Micropterus salmoides) ate the interloper, says the biologist who spotted the transgenic animal, Quenton Tuckett of the University of Florida. Brazil is proving more hospitable. Andre Magalhaes, a biologist at the Federal University of Sao Joao del-Rei's main campus, first spotted groups of the engineered zebrafish swimming in the Paraiba do Sul River Basin in 2015, in slow-moving creeks. The waters border the largest ornamental aquaculture center of Latin America, in Muriae, and Magalhaes says the fish probably escaped some of the center's 4500 ponds, which release water into the streams. Unlike Florida, the Brazilian creeks don't have any local predators for zebrafish, and Magalhaes believes they are now thriving. In 2017 he and colleagues began to survey five creeks in three municipalities, finding transgenic zebrafish in all of them. Every 2 months over 1 year, they collected and measured the animals and their eggs and analyzed their stomach content to see what they were eating. The fish are reproducing all year round, with a peak during the rainy season--just as native zebrafish do in Asia. But the transgenic fish seem to achieve sexual maturity earlier than their forebears, which allows them to reproduce more and spread faster. The invaders are also eating well: a diversified diet of native insects, algae, and zooplankton, the researchers reported this week in Studies on Neotropical Fauna and Environment. "They are in the first stages of invasion with potential to keep going," Magalhaes says. Before long, he says, the fish could become plentiful enough to directly affect local species by competing for food or preying on them. Despite Brazil's ban on sales of the fish, local farms keep breeding them, and stores all over the country sell them as pets. They may soon colonize other parts of the country: Isolated Glofish individuals were spotted in ponds and streams in south and northeast Brazil in 2020. Tuckett, whose lab in Florida is close to U.S. farms that grow hundreds of thousands of glowing fish, says the Brazilian detection "should be a wake-up call" for fish producers and natural resource managers in Brazil. But he is not terribly worried about impacts. He suspects the transgenic fish will encounter predators as they move to larger bodies of water. And the animals' bright colors will make them vulnerable. For now, the glowing fish "could be considered little weeds growing up out of the concrete," Tuckett says. Magalhaes likes the metaphor, but points out that even little weeds can grow to cause a lot of damage. --------------------------------------------------------------------- doi: 10.1126/science.ada1221 Relevant tags: Plants & Animals About the author Sofia Moutinho Sofia Moutinho Twitter Author --------------------------------------------------------------------- More from news baby receiving oral vaccination drops against polio 17 Feb. 2022 In new setback for eradication campaign, poliovirus from Pakistan shows up in Africa By * Leslie Roberts A raccoon dog's face 17 Feb 2022 Wild animals prized as delicacies in China contain a bevy of threatening viruses By * Jon Cohen Dr. Alondra Nelson at podium with President Joe Biden seated at right. 17 Feb. 2022 Resignation leads to controversial division of White House science adviser's job By * Jeffrey Mervis View more Got a tip for Science's news department? Connect ScienceInsider baby receiving oral vaccination drops against polio 17 Feb. 2022By * Leslie Roberts In new setback for eradication campaign, poliovirus from Pakistan shows up in Africa A raccoon dog's face 17 Feb 2022By * Jon Cohen Wild animals prized as delicacies in China contain a bevy of threatening viruses Dr. Alondra Nelson at podium with President Joe Biden seated at right. 17 Feb 2022By * Jeffrey Mervis Resignation leads to controversial division of White House science adviser's job An older man in a hospital gown and mask looks out a window 16 Feb 2022By * Meredith Wadman COVID-19 patients face higher risk of brain fog and depression, even 1 year after infection View more Sifter Artist's rendering of a long-necked sauropod dinosaur 11 Feb 2022By * Tess Joosse Sick dinosaur may have had the earliest known cough a female chimpanzee applies an insect to a wound on a male chimpanzee's face 8 Feb 2022By * Tess Joosse Chimps 'treat' each other's wounds with insects Bat flying out of cave 6 Dec 2021By * Rachel Fritts Baby bats learn to navigate by hitching a ride on mom davemaoite 12 Nov 2021By * Paul Voosen This diamond contains a mineral never before seen in nature View more RecommendedClose LettersNovember 2002 Transgenic Fish: A Boon or Threat? In DepthJanuary 2019 Ships banned from throwing unwanted fish overboard LettersNovember 2015 Brazilian aquatic biodiversity in peril In DepthAugust 2019 Brazilian president attacks deforestation data Subscribe to News from Science Don't yet have access? Subscribe to News from Science for full access to breaking news and analysis on research and science policy. Subscribe Support nonprofit science journalism Help News from Science publish trustworthy, high-impact stories about research and the people who shape it. Please make a tax-deductible gift today. Donate [logo-dark] x ( ) $25 (*) $50 ( ) $100 ( ) Other $ [ ] Please enter a valid email (*) Single ( ) Monthly Email: [ ] Please enter a valid email Country: [United States ] [ ] I also wish to receive emails from AAAS/Science and Science advertisers, including information on products, services and special offers which may include but are not limited to news, careers information & upcoming events. Donate now Support nonprofit science journalism If we've learned anything from the COVID-19 pandemic, it's that we cannot wait for a crisis to respond. Science and AAAS are working tirelessly to provide credible, evidence-based information on the latest scientific research and policy, with extensive free coverage of the pandemic. Your tax-deductible contribution plays a critical role in sustaining this effort. Charitable Disclosures Loading... Skip slideshow Follow Us * * * * * * * NEWS * All News * ScienceInsider * News Features * Subscribe to News from Science * News from Science FAQ * About News from Science * CAREERS * Careers Articles * Find Jobs * Employer Profiles * COMMENTARY * Opinion * Analysis * Blogs * JOURNALS * Science * Science Advances * Science Immunology * Science Robotics * Science Signaling * Science Translational Medicine * Science Partner Journals * AUTHORS & REVIEWERS * Information for Authors * Information for Reviewers * LIBRARIANS * Manage Your Institutional Subscription * Library Admin Portal * Request a Quote * Librarian FAQs * ADVERTISERS * Advertising Kits * Custom Publishing Info * Post a Job * RELATED SITES * AAAS.org * AAAS Communities * EurekAlert! * Science in the Classroom * ABOUT US * Leadership * Work at AAAS * Prizes and Awards * HELP * FAQs * Access and Subscriptions * Order a Single Issue * Reprints and Permissions * Contact Us Follow Us * * * * * * AAAS logo (c) 2022 American Association for the Advancement of Science. All rights reserved. AAAS is a partner of HINARI, AGORA, OARE, CHORUS, CLOCKSS, CrossRef and COUNTER. back to top * Terms of Service * Privacy Policy * Accessibility Thank you for reading News fromScience. You have reached your limit of 5 free news stories in the past 30 days. To gain unlimited access to News fromScience, pleaseLog inor subscribe to News from Science. AAAS Members canLog infor unlimited access. $2.99/Month$25/YearFrequently Asked Questions