Preliminary genetic evidence of two different populations of Opisthorchis viverrini in Lao PDR
Opisthorchis viverrini is a major public health concern in Southeast Asia. Various reports have suggested that this parasite may represent a species complex, with genetic structure in the region perhaps being dictated by geographical factors and different species of intermediate hosts. We used four microsatellite loci to analyze O. viverrini adult worms originating from six species of cyprinid fish in Thailand and Lao PDR. Two distinct O. viverrini populations were observed. In Ban Phai, Thailand, only one subgroup occurred, hosted by two different fish species. Both subgroups occurred in fish from That Luang, Lao PDR, but were represented to very different degrees among the fish hosts there. Our data suggest that, although geographical separation is more important than fish host specificity in influencing genetic structure, it is possible that two species of Opisthorchis, with little interbreeding, are present near Vientiane in Lao PDR.
KeywordsMicrosatellite DNA Opisthorchis viverrini Population genetics Host factors Cyprinid fish
This research was supported by the Thailand Research Fund through the Basic Research Grant and the Royal Golden Jubilee Ph.D. Program (grant PHD/0210/2550 to O.P.), and Higher Education Research Promotion and National Research University Project of Thailand, Office of the Higher Education Commission, through health cluster (SHeP-GMS), as well at the National Institutes of Health (R21AI104513). We acknowledge the support of the Faculty of Medicine, Khon Kaen University Visiting International Professor Program. We also wish to thank the Office of Research Affairs and the Invitation Research fund from faculty of Medicine, Khon Kaen University, Thailand, and the Deutsche Forschungsgemeinschaft (grant PE1611/1-3) for the assistance. We acknowledge the support of the Cholangiocarcinoma Screening and Care Program, (CASCAP) Khon Kaen University, 40002, Thailand.
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Conflict of interest
The authors declare that they have no conflict of interest.
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