title: Multilocus sequence typing of Enterocytozoon bieneusi: Lack of geographic segregation and existence of genetically isolated sub-populations.
abstract: The population structure of Enterocytozoon bieneusi was examined by multilocus sequence typing (MLST) of 64 specimens from AIDS patients in Peru, Nigeria, and India and five specimens from captive baboons in Kenya using a combination of the ribosomal internal transcribed spacer (ITS) and four microsatellite and minisatellite markers. Parasites in different geographic locations (Peru, India, and Nigeria) all had strong and significant linkage disequilibrium (LD) and only limited recombination, indicative of a clonal population structure in E. bieneusi from each location. When isolates of various geographical areas were treated as a single population, phylogenetic analysis and substructural analysis using STRUCTURE found no evidence for the existence of geographically segregated sub-populations. Nevertheless, both analyses revealed the presence of two major genetically isolated groups of E. bieneusi: one (sub-population 1) contained all isolates of the anthroponotic ITS genotype A, whereas the other (sub-population 2) harbored isolates of multiple ITS genotypes with zoonotic potential. This was also supported by FST analysis. The measurement of LD and recombination rates indicated that sub-population 2 had a clonal population structure, whereas sub-population 1 had an epidemic population structure. The data confirmed the existence of genetic sub-populations in E. bieneusi that may be transmitted differently in humans.
authors.affiliation: Division of Foodborne, Waterborne and Environmental Diseases, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA 30333, USA.
authors.forename: Wei
authors.initials: W
authors.lastname: Li
authors.forename: Vitaliano
authors.initials: V
authors.lastname: Cama
authors.forename: Frederick O
authors.initials: FO
authors.lastname: Akinbo
authors.forename: Sandipan
authors.initials: S
authors.lastname: Ganguly
authors.forename: Nicholas M
authors.initials: NM
authors.lastname: Kiulia
authors.forename: Xichen
authors.initials: X
authors.lastname: Zhang
authors.forename: Lihua
authors.initials: L
authors.lastname: Xiao
mesh_terms: D000328:Adult; D000818:Animals; D002648:Child; D021901:DNA, Intergenic / Q000235:genetics; D021862:Enterocytozoon / Q000145:classification* / Q000235:genetics*; D005787:Gene Frequency; D005828:Genetics, Population; D005838:Genotype; D006801:Humans; D007194:India; D007630:Kenya; D008969:Molecular Sequence Data; D058885:Multilocus Sequence Typing; D009549:Nigeria; D010568:Peru; D010802:Phylogeny; D058974:Phylogeography; D011110:Polymorphism, Genetic
chemical_list: D021901:DNA, Intergenic