Molecular variation in Echinococcus.

In the past decade, molecular genetic approaches have revolutionised the study of population biology and taxonomy and have provided a vast accumulation of DNA sequence and other genetic data. DNA techniques, however, have only recently been applied to the study of helminth parasite populations yet, already, valuable information about population structure, genetic variation and phylogeny of the Echinococcus organisms is emerging. Some of this recently acquired molecular information is reviewed here, and its implications in terms of our understanding of variation and taxonomy within the genus Echinococcus emphasised. In particular, the current strain status of some geographically isolated populations of E. granulosus is discussed and the issue of inter- and intra-strain variability within E. granulosus examined.