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Detection of ornamental transgenic fish by real-time PCR and fluorescence microscopy


Numbers of ornamental transgenic fish are increasing, and some of them are illegally imported into Europe. The fish are modified to display different fluorescent colors under UV light. In this article, we propose real-time PCR methods to detect fish presenting green, yellow and red fluorescent coloring. The methods were tested with success and were able to detect illegally imported fish in two European countries. The article also discusses some practical information that can be useful for routine analysis. In addition, a real-time PCR test able to highlight the presence of fish DNA in general is proposed to check the amplifiability of the DNA extracted from common bony fish species of the teleost subclass. Finally, as the testing by PCR can take several days and rapid decisions must be taken with living organisms, we explored the potential of fluorescence microscopy as a screening test to determine whether animals are suspect or can be released.

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This research (Agreement RF 11/6242 UGM-MONITOR) was subsidized by the Federal Public Service for Public Health, Food Chain Safety and the Environment. Our thanks go to Mr. Denis Roulez, Mr. Julien Maljean and Ms. Gaelle Antoine of the Authentication and Traceability Unit of CRA-W for their technical assistance. We are grateful to Olivier Fumière from the EURL-AP for his help with collecting samples for specificity testing. We also thank Kelly Lardinois from the Federal Public Service for Public Health, Food Chain Safety and the Environment for fruitful collaboration on the testing of illegally imported fish. Finally, we express our gratitude to Lotte Hougs from the Danish Veterinary and Food Administration for her feedback concerning the positive samples detected with the methods proposed in this paper.

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Correspondence to Frédéric Debode.

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Debode, F., Marien, A., Ledoux, Q. et al. Detection of ornamental transgenic fish by real-time PCR and fluorescence microscopy. Transgenic Res 29, 283–294 (2020).

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  • Transgenic
  • Fish
  • Glofish
  • Fluorescent
  • GMO
  • Real-time PCR