title: Genetic diversity within Schistosoma haematobium: DNA barcoding reveals two distinct groups.
abstract: BACKGROUND
  Schistosomiasis in one of the most prevalent parasitic diseases, affecting millions of people and animals in developing countries. Amongst the human-infective species S. haematobium is one of the most widespread causing urogenital schistosomiasis, a major human health problem across Africa, however in terms of research this human pathogen has been severely neglected.
  
  
  RESULTS
  To elucidate the genetic diversity of Schistosoma haematobium, a DNA 'barcoding' study was performed on parasite material collected from 41 localities representing 18 countries across Africa and the Indian Ocean Islands. Surprisingly low sequence variation was found within the mitochondrial cytochrome oxidase subunit I (cox1) and the NADH-dehydrogenase subunit 1 snad1). The 61 haplotypes found within 1978 individual samples split into two distinct groups; one (Group 1) that is predominately made up of parasites from the African mainland and the other (Group 2) that is made up of samples exclusively from the Indian Ocean Islands and the neighbouring African coastal regions. Within Group 1 there was a dominance of one particular haplotype (H1) representing 1574 (80%) of the samples analyzed. Population genetic diversity increased in samples collected from the East African coastal regions and the data suggest that there has been movement of parasites between these areas and the Indian Ocean Islands.
  
  
  CONCLUSIONS
  The high occurrence of the haplotype (H1) suggests that at some point in the recent evolutionary history of S. haematobium in Africa the population may have passed through a genetic 'bottleneck' followed by a population expansion. This study provides novel and extremely interesting insights into the population genetics of S. haematobium on a large geographic scale, which may have consequence for control and monitoring of urogenital schistosomiasis.
authors.affiliation: Wolfson Wellcome Biomedical Laboratories, Department of Zoology, Natural History Museum, London, United Kingdom.
authors.forename: Bonnie L
authors.initials: BL
authors.lastname: Webster
authors.forename: Aiden M
authors.initials: AM
authors.lastname: Emery
authors.forename: Joanne P
authors.initials: JP
authors.lastname: Webster
authors.forename: Anouk
authors.initials: A
authors.lastname: Gouvras
authors.forename: Amadou
authors.initials: A
authors.lastname: Garba
authors.forename: Oumar
authors.initials: O
authors.lastname: Diaw
authors.forename: Mohmoudane M
authors.initials: MM
authors.lastname: Seye
authors.forename: Louis Albert Tchuem
authors.initials: LA
authors.lastname: Tchuente
authors.forename: Christopher
authors.initials: C
authors.lastname: Simoonga
authors.forename: Joseph
authors.initials: J
authors.lastname: Mwanga
authors.forename: Charles
authors.initials: C
authors.lastname: Lange
authors.forename: Curtis
authors.initials: C
authors.lastname: Kariuki
authors.forename: Khalfan A
authors.initials: KA
authors.lastname: Mohammed
authors.forename: J Russell
authors.initials: JR
authors.lastname: Stothard
authors.forename: David
authors.initials: D
authors.lastname: Rollinson
mesh_terms: D000349:Africa; D000818:Animals; D016000:Cluster Analysis; D058893:DNA Barcoding, Taxonomic; D018509:DNA, Helminth / Q000737:chemistry / Q000235:genetics; D003576:Electron Transport Complex IV / Q000235:genetics; D014644:Genetic Variation; D006239:Haplotypes; D006801:Humans; D007195:Indian Ocean Islands; D008297:Male; D024101:Mitochondrial Proteins / Q000235:genetics; D008969:Molecular Sequence Data; D009245:NADH Dehydrogenase / Q000235:genetics; D012548:Schistosoma haematobium / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D017422:Sequence Analysis, DNA
chemical_list: D018509:DNA, Helminth; D024101:Mitochondrial Proteins; D009245:NADH Dehydrogenase; D003576:Electron Transport Complex IV