The Genomics of Entamoebae: Insights and Challenges

Abstract

An organism’s genome provides vital information about its biology and evolution. The genome of Entamoeba histolytica was sequenced and assembled in 2005 and provided many insights into the biology of the pathogen. A number of additional E. histolytica genomes and those of pathogenic and nonpathogenic relatives have followed, a process aided in no small part by the advent of second-generation sequencing technology. However, assembling Entamoeba genomes has proven particularly challenging. A number of factors contribute to this, including the large number of repetitive elements in Entamoeba genomes, their complex karyotypes, and their highly biased nucleotide compositions. In spite of the challenges, these genomes have been highly informative about the biology and evolution of Entamoebae and comparative analyses of pathogenic and nonpathogenic species (in particular, pathogenic E. histolytica and nonpathogenic E. dispar) have shed light on key virulence genes and on important gene families. Further advances in genome sequencing technology may improve our ability to sequence these challenging genomes, which will advance our knowledge of the evolution of the genus and of the pathogenicity of E. histolytica.