title: Low Divergence of Clonorchis sinensis in China Based on Multilocus Analysis.
abstract: Clonorchis sinensis, an ancient parasite that infects a number of piscivorous mammals, attracts significant public health interest due to zoonotic exposure risks in Asia. The available studies are insufficient to reflect the prevalence, geographic distribution, and intraspecific genetic diversity of C. sinensis in endemic areas. Here, a multilocus analysis based on eight genes (ITS1, act, tub, ef-1a, cox1, cox3, nad4 and nad5 [4.986 kb]) was employed to explore the intra-species genetic construction of C. sinensis in China. Two hundred and fifty-six C. sinensis isolates were obtained from environmental reservoirs from 17 provinces of China. A total of 254 recognized Multilocus Types (MSTs) showed high diversity among these isolates using multilocus analysis. The comparison analysis of nuclear and mitochondrial phylogeny supports separate clusters in a nuclear dendrogram. Genetic differentiation analysis of three clusters (A, B, and C) showed low divergence within populations. Most isolates from clusters B and C are geographically limited to central China, while cluster A is extraordinarily genetically diverse. Further genetic analyses between different geographic distributions, water bodies and hosts support the low population divergence. The latter haplotype analyses were consistent with the phylogenetic and genetic differentiation results. A recombination network based on concatenated sequences showed a concentrated linkage recombination population in cox1, cox3, nad4 and nad5, with spatial structuring in ITS1. Coupled with the history record and archaeological evidence of C. sinensis infection in mummified desiccated feces, these data point to an ancient origin of C. sinensis in China. In conclusion, we present a likely phylogenetic structure of the C. sinensis population in mainland China, highlighting its possible tendency for biogeographic expansion. Meanwhile, ITS1 was found to be an effective marker for tracking C. sinensis infection worldwide. Thus, the present study improves our understanding of the global epidemiology and evolution of C. sinensis.
authors.affiliation: Guangdong Provincial Institute of Public Health, Guangdong Provincial Center for Disease Control and Prevention. Guangzhou, China ; Department of Parasitology, Zhongshan School of Medicine, Sun Yat-Sen University; Key Laboratory of Tropical Diseases Control, Sun Yat-sen University, Ministry of Education, Guangzhou, China.
authors.forename: Jiufeng
authors.initials: J
authors.lastname: Sun
authors.forename: Yan
authors.initials: Y
authors.lastname: Huang
authors.forename: Huaiqiu
authors.initials: H
authors.lastname: Huang
authors.forename: Pei
authors.initials: P
authors.lastname: Liang
authors.forename: Xiaoyun
authors.initials: X
authors.lastname: Wang
authors.forename: Qiang
authors.initials: Q
authors.lastname: Mao
authors.forename: Jingtao
authors.initials: J
authors.lastname: Men
authors.forename: Wenjun
authors.initials: W
authors.lastname: Chen
authors.forename: Chuanhuan
authors.initials: C
authors.lastname: Deng
authors.forename: Chenhui
authors.initials: C
authors.lastname: Zhou
authors.forename: Xiaoli
authors.initials: X
authors.lastname: Lv
authors.forename: Juanjuan
authors.initials: J
authors.lastname: Zhou
authors.forename: Fan
authors.initials: F
authors.lastname: Zhang
authors.forename: Ran
authors.initials: R
authors.lastname: Li
authors.forename: Yanli
authors.initials: Y
authors.lastname: Tian
authors.forename: Huali
authors.initials: H
authors.lastname: Lei
authors.forename: Chi
authors.initials: C
authors.lastname: Liang
authors.forename: Xuchu
authors.initials: X
authors.lastname: Hu
authors.forename: Jin
authors.initials: J
authors.lastname: Xu
authors.forename: Xuerong
authors.initials: X
authors.lastname: Li
authors.lastname: Xinbingyu
mesh_terms: D000818:Animals; D002415:Cats; D002681:China; D003004:Clonorchis sinensis / Q000145:classification / Q000235:genetics*; D004285:Dogs; D014644:Genetic Variation; D006239:Haplotypes; D006790:Host-Parasite Interactions; D015810:Linkage Disequilibrium; D058885:Multilocus Sequence Typing / Q000379:methods*; D010802:Phylogeny; D051381:Rats; D017207:Rats, Sprague-Dawley