Molecular markers represent a valuable source of information for insights into the population biology and taxonomy of elms. A knowledge of the amounts and partitioning of genetic and genotypic diversity is potentially useful for research programs aimed at understanding the Dutch elm disease pandemic. In this paper we review the available molecular data from European populations of elms, and concentrate on three issues. Firstly, we evaluate the published reports suggesting that elms are segmental tetraploids. Secondly, we discuss how molecular data have been, and can be, used to address some long running taxonomic arguments regarding the European elms. Finally, we summarize published studies documenting levels and partitioning of population genetic variation.
