title: Genetic diversity of Taenia saginata (Cestoda: Cyclophyllidea) from Lao People's Democratic Republic and northeastern Thailand based on mitochondrial DNA.
abstract: BACKGROUND
  Taenia saginata is a tapeworm found in cattle worldwide. Analysis of genetic diversity in different geographical populations of T. saginata not only helps to understand the origin, transmission and spread of this organism, but also to evaluate the selection pressures acting on T. saginata and how it is responding to them. However, there are few reports of the genetic variability of T. saginata populations in different regions of the world, including Lao PDR and Thailand. We report the genetic diversity of T. saginata populations in Lao PDR and northeastern Thailand together with sequences of T. saginata from other countries deposited in GenBank.
  
  
  RESULTS
  Mitochondrial cox1 sequence analysis revealed that 15 and 8 haplotypes were identified in 30 and 21 T. saginata isolates from Lao PDR and northeastern Thailand, respectively. Fifty-three haplotypes were identified from 98 sequences. Phylogenetic tree and haplotype network analyses revealed that global isolates of T. saginata were genetically divided into five groups (A, B, C1, C2 and D). Taenia saginata isolates from Lao PDR and northeastern Thailand belonged to either Group A or B. Taenia saginata from western Thailand clustered in groups C1, C2 and D, and populations from the northeast and western Thailand were found to be genetically distinct. Taenia saginata isolates in Lao PDR and Thailand were also found to be genetically diverse but the degree of genetic differentiation was low.
  
  
  CONCLUSIONS
  Taenia saginata populations from Lao PDR and northeastern Thailand are genetically distinct from the population in western Thailand and it is proposed that T. saginata has been dispersed by different transmission routes in Southeast Asia.
authors.affiliation: Department of Parasitology and Research and Diagnostic Center for Emerging Infectious Diseases, Faculty of Medicine, Khon Kaen University, Khon Kaen, 40002, Thailand.|Faculty of Medicine, Mahasarakham University, Maha Sarakham, 44000, Thailand.
authors.forename: Oranuch
authors.initials: O
authors.lastname: Sanpool
authors.affiliation: Department of Parasitology and Research and Diagnostic Center for Emerging Infectious Diseases, Faculty of Medicine, Khon Kaen University, Khon Kaen, 40002, Thailand.
authors.forename: Rutchanee
authors.initials: R
authors.lastname: Rodpai
authors.affiliation: Department of Parasitology and Research and Diagnostic Center for Emerging Infectious Diseases, Faculty of Medicine, Khon Kaen University, Khon Kaen, 40002, Thailand. pewpan@kku.ac.th.
authors.forename: Pewpan M
authors.initials: PM
authors.lastname: Intapan
authors.affiliation: Department of Parasitology and Research and Diagnostic Center for Emerging Infectious Diseases, Faculty of Medicine, Khon Kaen University, Khon Kaen, 40002, Thailand.
authors.forename: Lakkhana
authors.initials: L
authors.lastname: Sadaow
authors.affiliation: Faculty of Medicine, Mahasarakham University, Maha Sarakham, 44000, Thailand.
authors.forename: Tongjit
authors.initials: T
authors.lastname: Thanchomnang
authors.affiliation: Centre of Malariology, Parasitology and Entomology, Ministry of Health, Vientiane, Lao PDR.
authors.forename: Sakhone
authors.initials: S
authors.lastname: Laymanivong
authors.affiliation: Department of Parasitology and Research and Diagnostic Center for Emerging Infectious Diseases, Faculty of Medicine, Khon Kaen University, Khon Kaen, 40002, Thailand.
authors.forename: Wanchai
authors.initials: W
authors.lastname: Maleewong
authors.affiliation: Department of Parasitology, National Institute of Infectious Diseases, Ministry of Health, Labour and Welfare, Tokyo, 162-8640, Japan. hyamasak@nih.go.jp.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yamasaki
mesh_terms: D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000453:epidemiology / Q000469:parasitology*; D018509:DNA, Helminth / Q000235:genetics*; D004272:DNA, Mitochondrial / Q000235:genetics*; D014644:Genetic Variation; D006801:Humans; D007812:Laos; D010802:Phylogeny; D058974:Phylogeography; D041202:Taenia saginata / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification; D013622:Taeniasis / Q000453:epidemiology / Q000469:parasitology* / Q000662:veterinary*; D013785:Thailand / Q000453:epidemiology
chemical_list: D018509:DNA, Helminth; D004272:DNA, Mitochondrial
keywords: Beef tapeworm; Distribution; Genetic diversity; Haplotypes; Lao PDR; Taenia saginata; Thailand