Physical Mapping by Pulsed-Field Gel Electrophoresis

During the past few years, there has been intense activity in physically mapping the genomes of a variety of organisms, including human, mouse, Drosophila, Caenorhabditis elegans, Arabidopsis thaliana , and yeast. The considerable advances made in physically mapping these genomes has demanded the development of a technique capable of filling the niche between conventional Southern blotting and such approaches as somatic cell genetics and fluorescence in situ hybridization (FISH). Pulsed-field gel electrophoresis (PFGE) fills this niche, and since its inception in 1983, has evolved into a robust and reliable technique. PFGE was first used for electrophoretically karyotyping yeasts and protozoa, but with the advent of commercially available rare cutter restriction enzymes, the technique was soon used for the long-range physical mapping of bacterial, yeast, and eukaryotic genomes.