title: Multilocus sequence evaluation for differentiating species of the trematode Family Gastrothylacidae, with a note on the utility of mitochondrial COI motifs in species identification.
abstract: Amphistomiasis, a neglected trematode infectious disease of ruminants, is caused by numerous species of amphistomes belonging to six families under the Superfamily Paramphistomoidea. In the present study, four frequently used DNA markers, viz. nuclear ribosomal 28S (D1-D3 regions), 18S and ITS2 and mitochondrial COI genes, as well as sequence motifs from these genes were evaluated for their utility in species characterization of members of the amphistomes' Family Gastrothylacidae commonly prevailing in Northeast India. In sequence and phylogenetic analyses the COI gene turned out to be the most useful marker in identifying the gastrothylacid species, with the exception of Gastrothylax crumenifer, which showed a high degree of intraspecific variations among its isolates. The sequence analysis data also showed the ITS2 region to be effective for interspecies characterization, though the 28S and 18S genes were found unsuitable for the purpose. On the other hand, sequence motif analysis data revealed the motifs from the COI gene to be highly conserved and specific for their target species which allowed accurate in silico identification of the gastrothylacid species irrespective of their intraspecific differences. We propose the use of COI motifs generated in the study as a potential tool for identification of these species.
authors.affiliation: Department of Zoology, North-Eastern Hill University, Shillong 793 022, Meghalaya, India. Electronic address: sudeep.ghatani@gmail.com.
authors.forename: Sudeep
authors.initials: S
authors.lastname: Ghatani
authors.affiliation: Department of Zoology, North-Eastern Hill University, Shillong 793 022, Meghalaya, India. Electronic address: jolleneandrea@gmail.com.
authors.forename: Jollin Andrea
authors.initials: JA
authors.lastname: Shylla
authors.affiliation: Department of Zoology, North-Eastern Hill University, Shillong 793 022, Meghalaya, India. Electronic address: bishnuroy12@rediffmail.com.
authors.forename: Bishnupada
authors.initials: B
authors.lastname: Roy
authors.affiliation: Department of Zoology, North-Eastern Hill University, Shillong 793 022, Meghalaya, India. Electronic address: tandonveena@gmail.com.
authors.forename: Veena
authors.initials: V
authors.lastname: Tandon
mesh_terms: D000818:Animals; D001483:Base Sequence; D019143:Evolution, Molecular; D017238:Genes, Helminth; D050259:Genes, Mitochondrial; D020459:Genes, rRNA; D056426:Genetic Loci; D008969:Molecular Sequence Data; D058885:Multilocus Sequence Typing; D059372:Nucleotide Motifs; D010802:Phylogeny; D016415:Sequence Alignment; D013045:Species Specificity; D014200:Trematoda / Q000145:classification* / Q000235:genetics*
keywords: Amphistomiasis; Gastrothylacidae; Mitochondrial COI; Molecular identification; Ribosomal DNA; Sequence motifs