What is DNA barcoding?

DNA barcoding is a new technique that uses the variations in short, standardized gene regions can be used to identify known species and to discover new ones. This is possible because the variation within each species is low relative to the differences among species. Since its development in 2003, the application of this technology has grown from straightforward taxonomic identification to such fields as biodiversity monitoring and ecosystem reconstruction, with new uses emerging in public health, agriculture, economics and trade, and law enforcement.

Why is this information important?

Until now, biological specimens were identified using morphological features which in most cases required the assistance of an experienced professional taxonomist. If a specimen is damaged or fragmented, at an immature stage of development, or part of an undiscovered cryptic species, even specialists may be unable to make an identification. Barcoding solves these problems because non-specialists can obtain barcodes from tiny amounts of tissue, in many cases even when it has been cooked and prepared, or even digested. This is not to say that DNA barcoding is a replacement for traditional taxonomy -- rather, it simply provides taxonomists and non-specialists alike a tool to help make identifications quickly or at times when none would have previously been possible.

What is the difference between iBOL and CBOL, and how are they related to each other? What do these international initiatives hope to accomplish?

The International Barcode of Life project (iBOL) is an international DNA barcoding initiative based at the University of Guelph, Canada. It involves partner nodes in 25 countries and is dedicated to assembling the sequence library and technology necessary to identify organisms rapidly and inexpensively through DNA barcoding. iBOL's principal goal is to barcode 5 million specimens from 500,000 species within five years. The Consortium for the Barcode of Life (CBOL) is an international initiative devoted to promoting DNA barcoding as a global standard for the identification of biological species. CBOL supports working groups, training, workshops, conferences, networks, outreach, and other activities that promote barcoding. However, CBOL does not conduct any barcoding and does not support the generation of barcode data. CBOL is in charge of iBOL's Working Group for Outreach and Collaborations

These and other initiatives work within a collaborative "Barcoding Landscape"of projects, networks, labs and people to create a global DNA barcode reference library and to put this library to use for science and society.

What are DNA barcoders discovering?

In most cases, the species identifications coming from DNA barcodes match the identifications coming from morphological features. In some cases, barcodes are revealing 'cryptic' species that are distinct from each other, but were previously considered the same species. In other cases, specialists working in different geographic regions may have proposed different names for closely related species, but barcodes are suggesting that they may belong to a single species.

DNA barcoding is giving us a clearer picture of the variation within each species by allowing us to associate immature and mature species and the males and females of each species. Most species descriptions are based on the morphological characteristics of adults -- their size, shape, anatomical structure, color, and the features of their shells, bones, muscles and other parts. In contrast, DNA barcoding requires only a tiny tissue sample. Specimens can be identified at any stage of development from egg to adult. Some species show significant sexual dimorphism - that is, the male and female of a species can look very different. If you don't see them mating, it's hard to know which males and females belong to the same species.

Through these and other discoveries, DNA barcoding is opening new windows into the study of ecological relationships and the evolutionary process, and it's improving our understanding of how many species there are on Earth.

How is this technology being used?

DNA barcoding is a tool for both basic and applied research. In addition to the research issues described above, DNA barcoding is being tested as a way to identify species involved in legal and regulatory matters. For example, a significant percentage of fish filets and caviar being sold in markets and restaurants are mislabeled, either by accident or through intentional fraud. Some mislabeled fish may be health hazards. Fish filets are difficult to identify because they lack distinctive morphological features, but barcoding allows food inspectors to identify them from their DNA alone. Border inspectors are beginning to use DNA barcodes to control the introduction of agricultural pests, products made from endangered species, and plants and animals that could be environmentally hazardous invasives or carriers of diseases.

What if I want to learn more, or get involved?

This website is meant to provide you with an introduction to DNA barcoding and the Barcoding Landscape. We encourage you to follow the links to partners, projects, publications, press coverage and other information. You can also join http://Connect.BarcodeOfLife.net.