DNA barcoding is an invaluable tool in helping biologists understand biological diversity.
DNA analysis has once again helped researchers discover new insect species. In a study published in the international journal Freshwater Science, scientists from the NTNU University Museum and the University of Minnesota report the discovery of three non-biting midge species that are new to science.
“For centuries, humans have used outward appearances to identify and classify life on Earth, but we now have a new tool in our toolbox: a DNA library of the world’s species, with more than 300,000 species in a publicly available, international database,” says Torbjørn Ekrem, coordinator of NorBOL, the Norwegian network for DNA barcoding, and an associate professor at NTNU’s University Museum.
Will revolutionize research
Researchers believe this collection of what are called DNA barcodes, or short, species-specific DNA fragments, will revolutionize the science and management of biodiversity, and also contribute to increased food security and the control of trade in endangered species.
This is because DNA barcoding uses differences in genetic material to identify species. The method makes it possible for non-specialists to identify species with a great level of confidence, even if the material for analysis comes only from an organism’s remains.
The process involves comparing a short DNA sequence of an unknown organism to known sequences in a quality-assured reference library.
“If you get a hit in the database, then you know to which species the organism belongs. The assumption is, of course, that the species is already found in the database,” Ekrem said.
The advantage of DNA barcoding over traditional methods is that DNA barcodes makes it possible to identify species with just tiny tissue samples.
“An insect leg or a drop of blood, for example, is more than enough,” Ekrem said. “The barcodes can also be used to identify unknown life stages and distinguish between species that look very similar (as in the ruby-tailed wasps above). Many of these so-called cryptic species may have their own important role in the ecosystem or be specific pests. That makes it very important to distinguish them from one another in both research and management.”
Using DNA barcodes to identify species is of great importance for biodiversity research. The technology standardizes how species are identified and makes data and results comparable across borders and disciplines to a much greater extent than before.
“Because an organisms ‘leaves’ a little of its own DNA in the environment it lives in, it is also possible to find species that live in a lake, for example, by taking samples of the water. This is particularly useful for monitoring rare and endangered species. Species are the most important biological unit in the study of biodiversity, and DNA barcodes have been shown to be an important tool in conducting research on genetic differences between closely related species and subspecies,” says Ekrem.
Ekrem says that the natural diversity that surrounds us is not only fascinating but is absolutely crucial in maintaining modern society.
“Think of food production, pollination, fishing and clothing production,” he says. “We need efficient and precise tools for understanding biodiversity. DNA barcoding has come to be the best tool for the job.”
Norwegian DNA database
Norway has a national network for DNA barcoding that is composed of 16 institutions. These different groups are all working to add to the “national library” of DNA barcodes from Norwegian species.
“This effort is partly funded by the Norwegian Biodiversity Information Centre and has so far been relatively limited in scope. However, we have recently received substantial funding from the Research Council of Norway to develop the network into a full-scale national research infrastructure. The goal is to record 20,000 species in five years. So far, we have 3,500 species from Norway registered in the database,” Ekrem says.
The Norwegian network NorBOL is linked to the world’s largest international project on biodiversity, so that Norwegian scientists record all their data in a common, open international database. Animals, plants and fungi know no borders, a fact that makes it important to work closely with participating nations.
“Our contribution to the project has given us some international visibility,” says Ekrem.
The NTNU University Museum and the University Museum of Bergen, with support from the Norwegian Environment Agency, held capacity building courses with participants from Africa and Central America in the summer of 2013. NTNU is also working with the Norwegian Environment Agency to educate students from Myanmar in natural resource management. DNA barcoding will play a central role in this effort.