What are DNA barcodes used for?

DNA barcodes are a valuable tool for identifying specimens. They are also particularly useful for...

  • ...conservation. Species identification underpins all conservation efforts and DNA barcoding provides a rapid and accurate means of identifying species, thus providing a basis for biodiversity monitoring, habitat protection and environmental risk assessment


  • ...discerning cryptic species. Cryptic species are species which do not interbreed but whose morphology is similar, making them difficult or impossible to discern using morphological criteria alone. DNA barcodes have revealed cryptic species in diverse groups including butterflies, algae, orchids, and mollusks.


  • ...the identification of incomplete specimens. If only part of a specimen is available, such as a leaf fragment, pollen grain, the leg of an insect, or a tuft of hair, species identification based on morphology alone may not be possible. Such samples however, may be barcoded, thus making it possible to identify the species to which they belong.


  • ...associating males and females of the same species. In certain groups, males and females may be dimorphic (i.e. they may not look the same), making it difficult to know which males and females belong to the same species. Despite external differences, males and females belonging to the same species share a common DNA barcode, making it possible to use the barcode to assign males and females to the correct species.


  • ...associating life stages of the same species. In some groups, immature life stages may be phenotypically different from adult life stages of the same species, complicating the association between immatures and adults. Both immatures and adults belonging to a single species share a common barcode sequence, making it possible to use the barcode as a tool for associating life stages.


  • ...the identification of invasive species. Invasive species are species which originate in one region but which are inadvertently (or sometimes purposefully) introduced into another. Such species are often responsible for significant economic loss and sometimes pose a serious threat to native species. DNA barcoding may play a critical role in the rapid, early detection of invasives, fundamentally important to both outbreak prediction and species monitoring.


  • ...forensics. Crime scene investigations often use insect larval development or fragments of plant matter to determine when and where a crime was committed. In cases where such material is difficult to identify based on morphology, the DNA barcode provides an alternate means of identification.


  • ...international trade regulation. Products made from illegally obtained materials, such as illegally logged trees, are widely available on the international market. The source of the materials used in such products is often difficult to verify, making it difficult to know which geographic regions require further protection. DNA barcoding may be used to determine the identity and origin of such materials, with the goal of implementing protective measures and ultimately reducing the circulation of such goods on the market.


  • ...food security. The contents of products found in the supermarket may be difficult to verify, especially if the ingredients have been ground or otherwise processed. DNA barcoding, however, provides a means of identifying the contents of such products. Recent investigations using DNA barcoding have revealed that certain products, including natural health products and frozen lasagne, contain ingredients that are inconsistent with their package labeling. Other investigations have demonstrated extensive fraud in the seafood market, where cheaper fish is sometimes sold as a more expensive variety in order to increase its retail value.