20 years since the introduction of DNA barcoding: from theory to application

Abstract

Traditionally, taxonomic identification has relied upon morphological characters. In the last two decades, molecular tools based on DNA sequences of short standardised gene fragments, termed DNA barcodes, have been developed for species discrimination. The most common DNA barcode used in animals is a fragment of the cytochrome c oxidase (COI) mitochondrial gene, while for plants, two chloroplast gene fragments from the RuBisCo large subunit (rbcL) and maturase K (matK) genes are widely used. Information gathered from DNA barcodes can be used beyond taxonomic studies and will have far-reaching implications across many fields of biology, including ecology (rapid biodiversity assessment and food chain analysis), conservation biology (monitoring of protected species), biosecurity (early identification of invasive pest species), medicine (identification of medically important pathogens and their vectors) and pharmacology (identification of active compounds). However, it is important that the limitations of DNA barcoding are understood and techniques continually adapted and improved as this young science matures.

Discriminatory power of rbcL barcode locus for authentication of some of United Arab Emirates (UAE) native plants

“…DNA barcoding, a two decade old science reviewed extensively (Pecnikar and Buzan 2013;Ali et al 2014), has applications in many branches of science other than identification of organisms plants/animals. Some of the applied areas of barcoding are recognizing insect-host relationship (Jurado-Rivera et al 2009), analyzing the diet of herbivores (Valentini et al 2009;Staudacher et al 2011;Stech et al 2011), scrutinizing the components of herbal medicines (Srirama et al 2010), food products (Jaakola et al 2010) and in ecological forensics to identify the plant from a small tissue of root, or seedling or cryptic life stages (e.g., of fern gametophytes) and endangered species.…”

Macroalgas exoticas en la costa de Chile: patrones espaciales y temporales en el proceso de invasion

“…Además, el uso de nuevas herramientas moleculares como el "Código de Barras del ADN" ha permitido, entre otras cosas, identificar el real estatus taxonómico de numerosos taxa que habían sido mal identificados (Pečnikar & Buzan, 2014). En el caso de la costa chilena, la re-identificación de varias especies de macroalgas ha permitido encontrar una alta similitud en las secuencias genéticas con especies de la costa neozelandesa y australiana.…”

Barcoding in trypanosomes

“…Reliable: the primer binding sites should be highly conserved and/or multicopy, so the primers are still applicable for field samples that may have suffered a degree of DNA degradation. (Savolainen et al 2005;Ferri et al 2009;Valentini et al 2009;Pečnikar andBuzan, 2014) Valentini et al (2009) discussed the different requirements of DNA barcodes for different users, and highlighted the differences between DNA barcoding 'sensu stricto' and 'sensu lato'. DNA barcoding 'sensu stricto' is favoured by taxonomists and prioritizes standardization of primers with enough variation to elucidate a high level of phylogenetic information.…”

“…DNA barcoding 'sensu lato' is most suited to environmental samples and prioritizes short, robust primer binding sites that are resistant to degradation. groups has proved difficult, not least because the level of genetic variability possible within each species is poorly understood (Enyaru et al 2010), and consensus is yet to be reached regarding which genes to target and the criteria for delimiting species groups Pečnikar and Buzan, 2014).…”