Inter-individual and intragenomic variations in the ITS region of Clonorchis sinensis (Trematoda: Opisthorchiidae) from Russia and Vietnam

Tatonova Y.V., Chelomina G.N., Nguyen H.M.

В журнале Infection, Genetics and Evolution

Год: 2017 Номер: 55 Страницы: 350-357

Here we examined the intraspecific genetic variability of Clonorchis sinensis from Russia and Vietnam using nuclear DNA sequences (the 5.8S gene and two internal transcribed spacers of the ribosomal cluster). Despite the low level of variability in the ITS1 region, this marker has revealed some features of C. sinensis across multiple geographic regions. The genetic diversity levels for the Russian and Vietnamese populations were similar (0.1 and 0.09%, respectively) but were significantly lower than the C. sinensis from China (0.31%). About half of the sequences of the Chinese (53%) and Korean (47%) populations and about a tenth of the Vietnamese (12%) and Russian (8%) sequences included a 5 bp insertion. No sequences with nucleotide substitutions both upstream and downstream of the 5 bp insertion were found within the whole data set. The population of northern China had both sequence variants (with substitutions either upstream or downstream of the insertion), while only one of these variants was presented at the other localities. The Vietnamese population had a higher frequency of intragenomic polymorphism than the Russian population (69% vs. 46% and 23% vs. 3% at the 114 bp and 339 bp positions, respectively). These data are discussed in connection with parasite origin and adaptation, and also its invasive capacity and drug-resistance.

DOI 10.1016/j.meegid.2017.10.008