title: Mitochondrial DNA sequence and gene order of the Sri Lankan Schistosoma nasale is affiliated to the African/Indian group.
abstract: A 1.9 kb nucleotide sequence of part of the mitochondrial (mt) genome covering the cox1-trnT-rrnL-trnC-rrnS region, and the order of the remaining mitochondrial protein-coding genes for S. nasale of Sri Lankan origin, has been determined for analysis of the possible placement of this species in the genus Schistosoma. The gene order of this species is similar to that of the African and Indian Schistosoma species, but strikingly different from the East Asian species. Analysis of an alignment of the 1.9 kb sequence with available sequences from other schistosomes indicated affinities with S. spindale (found in Sri Lanka) and African species (in particular S. intercalatum and S. haematobium). Phylogenetic trees inferred from the alignment including 1 kb of RNA (transfer RNA and ribosomal RNA) sequence for 8 other Schistosoma spp. and Fasciola hepatica as an out-group revealed that S. nasale is placed proximally to S. spindale, S. intercalatum, S. haematobium and S. mansoni in the African sub-group while the East Asian species are more distant. S. incognitum lies basal to the combined African/Indian clade. The mtDNA analysis strongly supports the hypothesis that S. nasale is closely affiliated with the African/Indian schistosome group rather than the East Asian Schistosoma species.
authors.affiliation: Laboratory of Biomedical Science, Department of Veterinary Medicine, College of Bioresource Sciences, Nihon University, Fujisawa 252-8510, Japan.
authors.forename: Yukita
authors.initials: Y
authors.lastname: Sato
authors.forename: Thanh Hoa
authors.initials: TH
authors.lastname: Le
authors.forename: Reina
authors.initials: R
authors.lastname: Hiraike
authors.forename: Masayoshi
authors.initials: M
authors.lastname: Yukawa
authors.forename: Takeo
authors.initials: T
authors.lastname: Sakai
authors.forename: R P V Jayanthe
authors.initials: RP
authors.lastname: Rajapakse
authors.forename: Takeshi
authors.initials: T
authors.lastname: Agatsuma
mesh_terms: D000818:Animals; D001483:Base Sequence; D018509:DNA, Helminth / Q000032:analysis / Q000302:isolation & purification; D004272:DNA, Mitochondrial / Q000235:genetics*; D023061:Gene Order; D014644:Genetic Variation; D008969:Molecular Sequence Data; D010802:Phylogeny; D012547:Schistosoma / Q000145:classification* / Q000235:genetics*; D013188:Sri Lanka
chemical_list: D018509:DNA, Helminth; D004272:DNA, Mitochondrial