Assessment of the universality and utility of a set of conserved mitochondrial COI primers in insects

A set of mitochondrial COI primers has been studied by genomic PCR and many primer combinations shown to work universally well across Insecta. They are able to amplify various amplicons with different variability which enables the selection of a particular amplicon as a suitable DNA marker for a project. The potential usefulness of different amplicons is examined, with analysis on published study cases employing these regions. With respect to their variability, amplicons UEA5/UEA6, UEA7/UEA8 and UEA5/UEA8 could be useful for low- to mid-level phylogenetic analysis, i.e. from species, genus to perhaps family level depending on taxa involved. UEA5/UEA6 will be too conserved for intraspecific studies. Amplicons UEA3/UEA4 and UEA9/UEA10 would be better suited to low-level phylogenetic investigations, such as analysis of relationships among closely related species and population genetic studies. However, these guidelines should not be over-generalized for the reasons given. Amplification conditions of various primer combinations, and general problems in the use of conserved PCR primers are discussed.