A Comparison of Mitochondrial DNA Amplification Strategies for Species Identification

Forensic scientists are regularly presented with biological material of unknown origin, and determining if it is human or establishing what species it is can be critical to an investigation. Given this, several molecular methods have been developed for species identification of forensic samples, the most common of which is mtDNA amplification using universal primers followed by sequencing of the amplicon and comparison of the sequence to a database. In the current study, multiple mtDNA loci from a wide range of animal species were amplified using nine different universal primer pairs. Amplification success was measured, and a subset of amplicons was put through DNA sequencing to determine how effective each mtDNA locus was for species identification. Some loci amplified in a much wider range of species than did others, and smaller amplicons were more likely to amplify than were larger ones. However, there was a notable tradeoff between amplicon size and species identification success, wherein very small amplicons often failed to produce definitive species identification.