Variable and invariable DNA repeat characters revealed by taxonprint approach are useful for molecular systematics

A specially optimized restriction analysis of highly repetitive DNA element s, called DNA taxonprint, was applied for phylogenetic study of primates an d lizards. It was shown that electrophoretic bands of DNA repeats revealed by the taxonprint technique have valuable properties for molecular systemat ics. Approximately half of taxonprint bands (TB) are invariable and do not disappear from the genomes during evolution or change spontaneously. Presum ably these invariable bands are restriction fragments of dispersed DNA repe ats. Another group represents variable taxonprint bands that differ even be tween closely related species. These variable bands are probably represente d by tandem DNA repeats and could be used as species-specific markers. It w as shown that taxonprint bands are independent characters since the appeara nce of a new taxonprint band does not change the previous band pattern. Phy logenetic reconstruction carried out on taxonprint data demonstrated that t his approach could be of general utility for molecular systematics and spec ies identification.