Geographical genetic structure within the human lung fluke, Paragonimus westermani, detected from DNA sequences

Abstract

Nucleotide sequences were obtained for the second internal transcribed spacer of the ribosomal gene repeat and for part of the mitochondrial cytochrome c oxidase subunit I gene from geographical isolates of Paragonimus westermani from Japan, China, Korea, Taiwan, the Philippines, peninsular Malaysia and Thailand. Sequences were obtained from several other species of Paragonimus for comparative purposes. Two groups were recognized within P. westermani : an NE group (China, Japan, Korea, Taiwan) which was relatively uniform and included both diploid and triploid forms, and a southern group (Malaysia, Thailand, Philippines), members of which were genetically distant from one another. According to both ITS2 and COI data, genetic distances among P. westermani isolates equalled or exceeded those between some distinct species of Paragonimus. The ITS2 sequences were conserved relative to COI sequences. Substitutions among the latter may be approaching saturation within the genus Paragonimus.

Characterization of Fasciola gigantica isolates from cattle from South-western Zimbabwe using RAPD-PCR

“…However, it was possible to score relationships between some samples on the basis of their place of origin, in Group A and Group E we had isolates from Gwanda. The limited number of isolates in the present study and previous studies [28,29] perhaps missed the intraspecies phylogenetic structure. In Group D we have isolate 15 from Bulawayo and isolate 11 from Matopo which are not clustered, these isolates are completely separate from all the other isolates in the major cluster and this implies that they are substantially genetically different from the other isolates.…”

“…Previous studies [28,29] focusing on geographic comparisons showed low divergence among isolates. Our cluster analysis did not show a relationship among F. gigantica isolates and their geographical location.…”

Use of ITS rDNA for discriminating of larval stages of two microphallid (Digenea) species using Hydrobia ulvae (Pennant, 1777) and Corophium volutator (Pallas, 1766) as intermediate hosts

“…Due to its conserved nature, the ITS2 region is a sensitive and reliable diagnostic marker at the species or genus level (Adlard et al 1993;Kane and Rollinson 1994;Blair et al 1997aBlair et al , 1997b. In comparison, the ITS1 region is far more variable and therefore useful for investigating intra-specific patterns of variation.…”

Paragonimus Heterotremus Infection in Nagaland: A New Focus of Paragonimiasis in India

“…[8,7] To be more precise, the primers used were 3S (forward, 5'-GGTACCGGTGGATCACTCGGCTCGTG-3') [9] and A28 (reverse, 5'-GGGATCCTGGTTAGTTTCTTTTCCTCCGC-3'). [10] The PCR amplification was performed using 0.25 µm of each primer and 2.5 U of Taq polymerase (Invitrogen Corp., Carlsbad, CA, USA). The amplified products were extracted from agarose gels (Lonza, Rockland, ME, USA) and sequenced using the corresponding primers and the BigDye Terminator Cycle Sequencing kit (Applied Biosystems, Foster City, CA, USA) on an automated sequencer (ABI 310 Genetic Analyzer; Applied Biosystems).…”