Genomic Approaches to Uncovering the Coevolutionary History of Parasitic Lice

Abstract

Next-generation sequencing technologies are revolutionizing the fields of genomics, phylogenetics, and population genetics. These new genomic approaches have been extensively applied to a major group of parasites, the lice (Insecta: Phthiraptera) of birds and mammals. Two louse genomes have been assembled and annotated to date, and these have opened up new resources for the study of louse biology. Whole genome sequencing has been used to assemble large phylogenomic datasets for lice, incorporating sequences of thousands of genes. These datasets have provided highly supported trees at all taxonomic levels, ranging from relationships among the major groups of lice to those among closely related species. Such approaches have also been applied at the population scale in lice, revealing patterns of population subdivision and inbreeding. Finally, whole genome sequence datasets can also be used for additional study beyond that of the louse nuclear genome, such as in the study of mitochondrial genome fragmentation or endosymbiont function.

Keywords: Phthiraptera; cryptic species; endosymbionts; mitochondrial genomes; phylogenomics; population genomics.

Figure 1

Overview of high-throughput sequencing pipelines as they have been applied to parasitic lice in fields of genome assembly, phylogenomics, and population genomics. Louse image credit Kosta Mumcuoglu (vectorized by T. Michael Keesey) Creative Commons Attribution-ShareAlike 3.0 Unported license.