RESTRICTION-ENDONUCLEASE ANALYSIS OF HIGHLY REPETITIVE DNA AS A PHYLOGENETIC TOOL

Multiple band patterns of DNA repeats in the 20-500-nucleotide range c an be detected by digesting genomic DNA with short-cutting restriction endonucleases, followed by end labeling of the restriction fragments and fractionation in nondenaturing polyacrylamide gels. We call such b and patterns obtained from genomic DNA ''taxonprints'' (Fedorov et al. 1992). Here we show that taxonprints for the taxonomic groups studied (mammals, reptiles, fish, insects-altogether more than 50 species) ha ve the following properties: (1) All individuals from the same species have identical taxonprints. (2) Taxonprint bands can be subdivided in to those specific for a single species and those specific for groups o f closely related species, genera, and even families. (3) Each restric tion endonuclease produces unique band patterns; thus, five to ten res triction enzymes (about 100 bands) may be sufficient for a statistical treatment of phylogenetic relationships based on polymorphisms of res triction endinuclease sites. We demonstrate that taxonprint analysis a llows one to distinguish closely related species and to establish the degree of similarity among species and among genera, ?these characteri stics make taxonprint analysis a valuable tool for taxonomic and phylo genetic studies.