New database for fish identification

Reliable DNA reference sequences for reliable fish identification

For some years now, Germany has employed validated DNA methods for checking the labelling of fish and crustaceans that are sold on the market or as prepared dishes in restaurants. The testing labs first isolate and cleanse DNA from the muscle tissue of the fish filet and then amplify a selected gene fragment by polymerase chain reaction (PCR). The PCR product thus obtained is next subjected to sequencing, transferring the sequence to a readable form. Finally, the sample sequence is compared with a collection of known DNA reference sequences of fish species, which are freely-accessible on public gene databases. If the sequence of the fish sample shows a high correlation with the sequence of a certain fish species, the sample is deemed identified and characterised as that fish species.

Before conducting the precise PCR sequence analysis, it must be ascertained that the DNA reference sequence to be used in characterising the fish species really is correct. In order to ensure the highest possible degree of certainty with regard to valid DNA sequences, the Federal Ministry of Food and Agriculture (BMEL) funded a sub-project entitled AutoMAT (the collaborative project "Development of innovative and non-invasive monitoring systems for fisheries research”). Together with the Thünen Institute, Aquagene (www.aquagene.org) was created, an open-access database currently containing 488 fish species with the DNA sequences of four different genetic markers. It is managed by Thünen’s Institute of Fisheries Ecology (https://www.thuenen.de/en/fi/projects/fish-identification-by-genetic-barcoding/).

Project period: 07/2013 to 12/2015