A team of researchers from Galicia in Spain have used forensic mitochondrial DNA species identification techniques to distinguish between sardines and horse mackerel. This method makes it possible to genetically differentiate between the fish, even if they are canned or processed, which makes it easier to monitor the degree to which fisheries resources are being exploited.
DNA from the mitochondria cell organelles is ideal for distinguishing between species. One of its components in particular, cytochrome b, is a genetic marker that scientists use to establish relationships between genera and families, and is also used by some forensic laboratories to identify animals that appear at crime scenes (cats or insects, for example).
Now, for the first time, researchers from the National Association of Manufacturers of Canned Fish and Shellfish (ANFACO-CECOPESCA, Spain) have used this technique in order to genetically identify small pelagic (non-coastal) species, such as sardines and horse mackerel. This study was supported by the European Fisheries Fund (EFF) and Spain's Ministry of the Environment and Rural and Marine Affairs (MARM).
"These molecular tools represent a great step forward for the sector, since they enable fisheries imports to be monitored and tracked, and also ensure they are correctly labelled", Montserrat Espieira, a biologist for ANFACO-CECOPESCA and lead researcher of the study, tells SINC.
By using this method, the team was able to identify more than 20 species from the sardine group (genera such as Sardina, Sardinella, Clupea, Ophistonoma and Ilisha) and a similar number of horse mackerel species (Trachurus, Caranx, Mullus, Rastrelliger and others), originating from seas all over the world.
The methodology involved gathering a sample of mitochondrial DNA from the fish (even if it was canned or processed), amplifying a fragment of cytochrome b (using a polymerase chain reaction PCR) and, lastly, car
FECYT - Spanish Foundation for Science and Technology