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Species detection

Monitoring of aquatic species can be challenging. Some cryptic or rare species are extremely difficult to capture or observe using traditional methods. With the eDNA approach, it is possible to confirm the presence of a particular species in a water body which means a revolutionary breakthrough for the monitoring of such species.

The eDNA approach focuses on the DNA species leave behind in the water. This eDNA is collected by sampling the water body. The often quite small amount of DNA is then amplified by a polymerase chain reaction (PCR). By using species-specific primers that only bind to the DNA of the target species, the presence of the species is shown by a bar that appears on the gel on which the results are viewed.

For more information on single-species detection and species for which primers are available, click here.

Multispecific approach

The eDNA technique can also be used to generate a complete list of species from a water sample for a specific group of species. For example, we can establish which fish or amphibian species occur in a water body. Universal primers are used to amplify all the DNA of one group in the water sample using PCR. With next generation sequencing (NGS), all amplified pieces of DNA are encoded and stored in a large data file. Those DNA codes are then compared to the DNA codes in our reference database. For each piece of DNA, the computer calculates from which species it originates, thereby generating a list of species.

In the future, we hope it will be possible to estimate a species density in a water body using the environmental DNA approach (see Research).

For more information about using environmental DNA in a multi-specific approach, click here.