Traditional molecular systematic studies have progressed by sequencing genes one by one, a time- and cost-intensive task that has limited the amount of data a researcher could feasibly obtain. With the continual improvement of next-generation sequencing technologies, however, obtaining large molecular data sets is becoming much easier, and much cheaper. This increase in data means, in many cases, increased accuracy in reconstructing the evolutionary history of organisms.
As phylogenetic studies advance to include progressively more sequence data, new techniques are being developed to obtain such data sets. While it would be ideal to simply sequence entire genomes, this is not yet feasible across large numbers of taxa. Instead, current methods are being developed that allow researchers to target specific genomic regions of interest for the organisms being studied.
Scientists at the University of Idaho and Oberlin College have developed one such method to obtain large, phylogenomic data sets. "This method utilizes long PCR, or long-range PCR, to strategically generate DNA templates for next-generation sequencing," explains Simon Uribe-Convers, graduate student and lead author. The protocol is available for free viewing in the January issue of Applications in Plant Sciences.
Long-range PCR is a method that allows for the amplification of much larger fragments of DNA than is possible with traditional PCRfragments larger than 40 kilobases have been reported in long PCR, versus fewer than 10 kilobases for traditional PCR. The authors of this study have developed a universal primer set across flowering plants that amplifies 315 kilobase fragments, which can then easily be sequenced using recently developed next-generation sequencing technologies. Uribe-Convers and colleagues tested this approach by amplifying chloroplast genomes for 30 species across f
|Contact: Beth Parada|
American Journal of Botany