Phylogenetic analysis of Trypanosomatina (Protozoa : Kinetoplastida) basedon minicircle conserved regions

Phylogenetic relationships within the suborder Trypanosomatina were inferre d from the kinetoplast DNA minicircle conserved region sequences. Trees bui lt using distance-matrix (Neighbor-Joining) acid maximum parsimony methods showed that the minicircle conserved regions (CRs) provide a sensitive and specific molecular marker suitable for phylogenetic analyses of subspecies and strains of trypanosomatid flagellates, as testified by the subdivision of the genus Leishmania into the subgenera Leishmania, Viannia and Saurolei shmania. However, since Phytomonas and monogenetic parasites of insects rep resent the earliest diverging groups, the CRs do not seem to be useful for inference of relationships among major lineages of the order Kinetoplastida .