Use and trends of molecular markers in sandflies (Diptera: Psychodidae)

The subfamily Phlebotominae is principally composed of the Lutzomyia and Phlebotomus genera: the main vectors of several protozoan, bacterial and viral pathogens. Since the 1990's molecular markers have enabled us to effectively address many issues concerning this taxon by, for example, solving systematic conflicts, increasing our understanding of speciation and host-parasite co-evolution, and determining the genetic structure of populations. In this paper we review the research undertaken using molecular markers in this taxonomic group. We hope that this will make it easier for scientists to identify markers and data analyses appropriate to their particular research interests. The principal trends we found are a move towards the use of mitochondrial DNA as molecular markers, DNA sequencing as the characterization method of choice, and phylogenetic analysis for analyzing the data. Most of the studies reviewed center on Lutzomyia longipalpis, the main vector for visceral leishmaniasis in the American tropics and Phlebotomus papatasi, the main vector for cutaneous leishmaniasis in Europe, Asia and Africa. Taxonomic problems and the description of genetic structure are the issues most addressed by researchers, followed by resolving systematic conflicts. Future research using molecular markers in the study of sandflies should be aimed towards: a) the development of genetic barcoding as a complementary tool for morphological identification and b) genome sequencing to increase our understanding of host-parasite interactions.