Genetic studies Across North America: Total evidence approach - mitochondrial control region - lake comparisons - Lake Erie Structure
Rex Meade Strange, Carol A. Stepien
DNA techniques are increasingly used as diagnostic tools in many fields and venues. In particular, a relatively new application is its use as a check for proper advertisement in markets and on restaurant menus. The identification of fish from markets and restaurants is a growing problem, as economic practices often render it cost- effective to substitute one species for another. DNA sequences that are diagnostic for many commercially important fishes are now documented on public databases, such as the National Center for Biotechnology Information’s (NCBI) GenBank. It is now possible for most genetics laboratories to identify the species a tissue sample was taken from without sequencing all the possible taxa it might represent. We decided to attempt to identify the species of the fish, despite our initial misgivings as to whether useful amounts of DNA could be extracted from deep-fried material. Herein, we outline a procedure using molecular tools and analysis that allows the identification of any species for which sequences are documented on GenBank. Our extraction procedure yielded DNA usable for PCR and subsequent sequencing, although the extractions were degraded and of relatively low molecular weight. Thirteen complete cytochrome b sequences representing all three species of Perca were found documented on GenBank. Three of our five samples matched one of the cytochrome b sequences of the yellow perch Perca flavescens, and two matched sequences from the European perch P. fluviatilis.
Figure 1. Phylogenetic relationships among Perca and outgroup mtDNA haplotypes as inferred from cytochrome b sequence divergences. Taxon labels are consistent with those in Table 1. * = correspondence to individual unknown fillet samples sequenced in this study. Numbers at nodes indicate percent support from 1000 bootstrap pseudo-replications.
Genetic studies Across North America: Total evidence approach - mitochondrial control region - lake comparisons - Lake Erie Structure
