title: A preliminary analysis of the population genetics and molecular phylogenetics of Onchocerca volvulus (Nematoda: Filarioidea) using nuclear ribosomal second internal transcribed spacer sequences.
abstract: Nuclear internal transcribed spacer 2 (ITS2) rDNA sequences were used for a molecular phylogenetics analysis of five Onchocerca species. The sister species of the human parasite O. volvulus was found to be the cattle parasite O. ochengi and not O. gibsoni, contrary to chromosomal evidence. The genetic differentiation of two African populations (representing the two African strains) and a Brazilian population of O. volvulus was also studied. Phylogenetic and network reconstruction did not show any clustering of ITS2 alleles on geographic or strain grounds. Furthermore, population genetics tests showed no indication of population differentiation but suggested gene flow among the three populations.
authors.affiliation: Laboratório de Evolução Molecular, Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, 4150-180, Portugal. rmhojas@ibmc.up.pt
authors.forename: Ramiro
authors.initials: R
authors.lastname: Morales-Hojas
authors.forename: Robert A
authors.initials: RA
authors.lastname: Cheke
authors.forename: Rory J
authors.initials: RJ
authors.lastname: Post
mesh_terms: D000818:Animals; D001483:Base Sequence; D002417:Cattle; D018509:DNA, Helminth / Q000235:genetics*; D021903:DNA, Ribosomal Spacer / Q000235:genetics*; D014644:Genetic Variation / Q000235:genetics*; D006801:Humans; D008969:Molecular Sequence Data; D017181:Onchocerca volvulus / Q000235:genetics*; D010802:Phylogeny; D014158:Transcription, Genetic / Q000235:genetics*
chemical_list: D018509:DNA, Helminth; D021903:DNA, Ribosomal Spacer