A universal DNA mini-barcode for biodiversity analysis
1 Biodiversity Institute of Ontario, University of Guelph, Guelph, Ontario, N1G 2W1, Canada
2 Human Cancer Genetics Program, The Ohio State University, Columbus OH 43210, USA
3 Research Centre, Agriculture and Agri-Food Canada, Ottawa, Ontario K1A 0C6, Canada
4 Department of Biology, Concordia University, 7141 Sherbrooke Street, Montreal, Quebec H4B 1R6, Canada
BMC Genomics 2008, 9:214 doi:10.1186/1471-2164-9-214Published: 12 May 2008
The goal of DNA barcoding is to develop a species-specific sequence library for all eukaryotes. A 650 bp fragment of the cytochrome c oxidase 1 (CO1) gene has been used successfully for species-level identification in several animal groups. It may be difficult in practice, however, to retrieve a 650 bp fragment from archival specimens, (because of DNA degradation) or from environmental samples (where universal primers are needed).
We used a bioinformatics analysis using all CO1 barcode sequences from GenBank and calculated the probability of having species-specific barcodes for varied size fragments. This analysis established the potential of much smaller fragments, mini-barcodes, for identifying unknown specimens. We then developed a universal primer set for the amplification of mini-barcodes. We further successfully tested the utility of this primer set on a comprehensive set of taxa from all major eukaryotic groups as well as archival specimens.
In this study we address the important issue of minimum amount of sequence information required for identifying species in DNA barcoding. We establish a novel approach based on a much shorter barcode sequence and demonstrate its effectiveness in archival specimens. This approach will significantly broaden the application of DNA barcoding in biodiversity studies.