{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,2]],"date-time":"2026-07-02T14:30:39Z","timestamp":1783002639883,"version":"3.54.5"},"reference-count":29,"publisher":"MDPI AG","issue":"20","license":[{"start":{"date-parts":[[2023,10,13]],"date-time":"2023-10-13T00:00:00Z","timestamp":1697155200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Mahasarakham University","award":["TUFF53\/2566"],"award-info":[{"award-number":["TUFF53\/2566"]}]},{"name":"Mahasarakham University","award":["S22093"],"award-info":[{"award-number":["S22093"]}]},{"name":"Thailand Science Research and Innovation Fundamental Fund","award":["TUFF53\/2566"],"award-info":[{"award-number":["TUFF53\/2566"]}]},{"name":"Thailand Science Research and Innovation Fundamental Fund","award":["S22093"],"award-info":[{"award-number":["S22093"]}]},{"name":"Japan Society for the Promotion of Science (JSPS) for research in Japan","award":["TUFF53\/2566"],"award-info":[{"award-number":["TUFF53\/2566"]}]},{"name":"Japan Society for the Promotion of Science (JSPS) for research in Japan","award":["S22093"],"award-info":[{"award-number":["S22093"]}]},{"name":"Department of Environmental Medicine, Kochi Medical School, Japan","award":["TUFF53\/2566"],"award-info":[{"award-number":["TUFF53\/2566"]}]},{"name":"Department of Environmental Medicine, Kochi Medical School, Japan","award":["S22093"],"award-info":[{"award-number":["S22093"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>Opisthorchiasis and clonorchiasis are prevalent in Southeast and Far-East Asia, which are caused by the group 1 carcinogenic liver flukes Opisthorchis viverrini sensu lato and Clonorchis sinensis infection. There have been comprehensive investigations of systematics and genetic variation of these liver flukes. Previous studies have shown that O. viverrini is a species complex, called \u201cO. viverrini sensu lato\u201d. More comprehensive investigations of molecular systematics and population genetics of each of the species that make up the species complex are required. Thus, other polymorphic genetic markers need to be developed. Therefore, this study aimed to characterize the intron regions of taurocyamine kinase gene (TK) to examine the genetic variation and population genetics of O. viverrini and C. sinensis collected from different geographical isolates and from a range of animal hosts. We screened seven intron regions embedded in TK. Of these, we selected an intron 5 of domain 1 (TkD1Int5) region to investigate the genetic variation and population genetics of theses liver flukes. The high nucleotide and haplotype diversity of TkD1Int5 was detected in O. viverrine. Heterozygosity with several insertion\/deletion (indel) regions were detected in TkD1Int5 of the O. viverrine samples, whereas only an indel nucleotide was detected in one C. sinensis sample. Several O. viverrine samples contained three different haplotypes within a particular heterozygous sample. There were no genetic differences between C. sinensis isolated from various animal host. Heterozygous patterns specifically detected in humans was observed in C. sinensis. Thus, TkD1Int5 is a high polymorphic genetic marker, which could be an alternative marker for further population genetic investigations of these carcinogenic liver flukes and other related species from a wide geographical distribution and variety of animal hosts.<\/jats:p>","DOI":"10.3390\/ani13203200","type":"journal-article","created":{"date-parts":[[2023,10,13]],"date-time":"2023-10-13T06:07:26Z","timestamp":1697177246000},"page":"3200","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Intron Regions as Genetic Markers for Population Genetic Investigations of Opisthorchis viverrini sensu lato and Clonorchis sinensis"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1872-1175","authenticated-orcid":false,"given":"Chairat","family":"Tantrawatpan","sequence":"first","affiliation":[{"name":"Division of Cell Biology, Department of Preclinical Sciences, Faculty of Medicine, and Center of Excellence in Stem Cell Research, Thammasat University, Rangsit Campus, Khlong Nueng 12120, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6726-3759","authenticated-orcid":false,"given":"Wanchai","family":"Maleewong","sequence":"additional","affiliation":[{"name":"Department of Parasitology, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand"},{"name":"Mekong Health Science Research Institute, Khon Kaen University, Khon Kaen 40002, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2604-0281","authenticated-orcid":false,"given":"Tongjit","family":"Thanchomnang","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, Mahasarakham University, Kham Riang 44000, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Warayutt","family":"Pilap","sequence":"additional","affiliation":[{"name":"Walai Rukhavej Botanical Research Institute, Mahasarakham University, Kham Riang 44150, Thailand"},{"name":"Center of Excellence in Biodiversity Research, Mahasarakham University, Kham Riang 44150, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1297-2117","authenticated-orcid":false,"given":"Takeshi","family":"Agatsuma","sequence":"additional","affiliation":[{"name":"Department of Environmental Medicine, Kochi Medical School, Kochi University, Oko, Nankoku 783-8505, Kochi, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ross H.","family":"Andrews","sequence":"additional","affiliation":[{"name":"Department of Surgery & Cancer, Faculty of Medicine, Imperial College, South Kensington Campus, London SW7 2AZ, UK"},{"name":"Cholangiocarcinoma Research Institute, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9480-1778","authenticated-orcid":false,"given":"Paiboon","family":"Sithithaworn","sequence":"additional","affiliation":[{"name":"Department of Parasitology, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand"},{"name":"Cholangiocarcinoma Research Institute, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4789-297X","authenticated-orcid":false,"given":"Weerachai","family":"Saijuntha","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, Mahasarakham University, Kham Riang 44000, Thailand"},{"name":"Center of Excellence in Biodiversity Research, Mahasarakham University, Kham Riang 44150, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,10,13]]},"reference":[{"key":"ref_1","unstructured":"WHO (1995). 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