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Sun M, Cheng Y, Gao C, Peng H, Wang N, Gu W, Lu D. Construction and characterization of microsatellite markers for the Schistosoma japonicum isolate from a hilly area of China based on whole genome sequencing. Parasitol Res 2023; 122:2737-2748. [PMID: 37710024 DOI: 10.1007/s00436-023-07976-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Accepted: 09/10/2023] [Indexed: 09/16/2023]
Abstract
Schistosoma japonicum had once caused the greatest disease burden in China and has still been transmitted in some hilly areas, for example, in Shitai of Anhui province, where rodents are projected to be the main reservoir. This may lead to a critical need of molecular tools with high efficiency in monitoring the dynamic of the rodent-associated S. japonicum, as an appropriate amount of schistosome input can re-establish its life cycle in a place with snails and then result in the re-emergence of schistosomiasis. Therefore, the goal of this study was to develop high polymorphic microsatellites from the whole genome of rodent-associated S. japonicum strain to monitor its transmission dynamic. We sampled the hilly schistosome isolate from Shitai of Anhui in China and sequenced the parasite with the next-generation sequencing technology. The whole genome was assembled with four different approaches. We then developed 71 microsatellite markers at a genome-wide scale throughout two best assembled genomes. Based on their chromosome mapping and the expected length of targeted sequences, we selected 24 markers for the development of multiplex reactions. Two multiplexes composed of 10 loci were finally developed, and their potential was revealed by their successful application on and capturing the genetic diversity of three schistosome populations. The selected 10 markers, each with clear chromosome location and characteristics, will be greatly useful in tracing the dispersal pathways or/and dynamics of the rodent-associated S. japonicum or others in the hilly area of China or elsewhere.
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Affiliation(s)
- Mengtao Sun
- Department of Epidemiology and Statistics, School of Public Health, Soochow University, Suzhou, China
| | - Yuheng Cheng
- Department of Epidemiology and Statistics, School of Public Health, Soochow University, Suzhou, China
| | - Changzhe Gao
- Department of Epidemiology and Statistics, School of Public Health, Soochow University, Suzhou, China
| | - Hanqi Peng
- Department of Epidemiology and Statistics, School of Public Health, Soochow University, Suzhou, China
| | - Ning Wang
- Department of Epidemiology and Statistics, School of Public Health, Soochow University, Suzhou, China
| | - Weiling Gu
- Jiaxing Center for Disease Control and Prevention, Jiaxing, Zhejiang, China.
| | - Dabing Lu
- Department of Epidemiology and Statistics, School of Public Health, Soochow University, Suzhou, China.
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2
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Wanlop A, Dang-Trinh MA, Kirinoki M, Suguta S, Shinozaki K, Kawazu SI. A simple and efficient miracidium hatching technique for preparing a single-genome DNA sample of Schistosoma japonicum. J Vet Med Sci 2022; 84:1108-1110. [PMID: 35732429 PMCID: PMC9412067 DOI: 10.1292/jvms.21-0536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
In this study, a simple and efficient miracidium hatching technique (MHT) protocol for
preparing a single-genome DNA of Schistosoma japonicum was proposed. The
protocol was designed with 96-well plates to collect a miracidium for single-genome DNA
preparation, and the effects of lighting conditions on hatching rates were evaluated. The
highest hatching rate was recorded under sunlight (92.4%), followed by fluorescent light
(88.0%), and the lowest rate was recorded under the dark condition (4.7%). The results
suggested for the first time, to our knowledge, that sunlight was efficient for this
simple MHT protocol. Successful amplification of microsatellite marker genes using DNA
isolated from a single miracidium also confirmed the quality of the single-genome DNA for
subsequent applications.
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Affiliation(s)
- Atcharaphan Wanlop
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine
| | | | - Masashi Kirinoki
- Department of Tropical Medicine and Parasitology, Dokkyo Medical University
| | - Saki Suguta
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine
| | - Kaho Shinozaki
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine
| | - Shin-Ichiro Kawazu
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine
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3
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Luo F, Yang W, Yin M, Mo X, Pang Y, Sun C, Zhu B, Zhang W, Yi C, Li Z, Wang J, Xu B, Feng Z, Huang Y, Lu Y, Hu W. A chromosome-level genome of the human blood fluke Schistosoma japonicum identifies the genomic basis of host-switching. Cell Rep 2022; 39:110638. [PMID: 35385741 DOI: 10.1016/j.celrep.2022.110638] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 12/22/2021] [Accepted: 03/16/2022] [Indexed: 12/20/2022] Open
Abstract
The evolution and adaptation of S. japonicum, a zoonotic parasite that causes human schistosomiasis, remain unclear because of the lack of whole-genome data. We construct a chromosome-level S. japonicum genome and analyze it together with 72 samples representing six populations of the entire endemic region. We observe a Taiwan zoophilic lineage splitting from zoonotic populations ∼45,000 years ago, consistent with the divergent history of their intermediate hosts. Interestingly, we detect a severe population bottleneck in S. japonicum, largely coinciding with human history in Asia during the last glacial maximum. We identify several genomic regions underlying natural selection, including GATAD2A and Lmln, both showing remarkable differentiation among different areas. RNAi knockdown suggests association of GATAD2A with parasite development and infection in definitive hosts, while Lmln relates to the specificity of the intermediate hosts. Our study provides insights into the evolution of S. japonicum and serves as a resource for further studies.
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Affiliation(s)
- Fang Luo
- Shanghai Institute of Infectious Disease and Biosecurity, State Key Laboratory of Genetic Engineering, Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, Ministry of Education Key Laboratory of Contemporary Anthropology, School of Life Science, Fudan University, Shanghai, China
| | - Wenbin Yang
- Shanghai Institute of Infectious Disease and Biosecurity, State Key Laboratory of Genetic Engineering, Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, Ministry of Education Key Laboratory of Contemporary Anthropology, School of Life Science, Fudan University, Shanghai, China
| | - Mingbo Yin
- Shanghai Institute of Infectious Disease and Biosecurity, State Key Laboratory of Genetic Engineering, Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, Ministry of Education Key Laboratory of Contemporary Anthropology, School of Life Science, Fudan University, Shanghai, China
| | - Xiaojin Mo
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Key Laboratory of Parasite and Vector Biology of China Ministry of Health, WHO Collaborating Centre for Tropical Diseases, Joint Research Laboratory of Genetics and Ecology on Parasite-host Interaction, Chinese Center for Disease Control and Prevention and Fudan University, Shanghai, China
| | - Yuhong Pang
- Biomedical Pioneering Innovation Center (BIOPIC) and Beijing Advanced Innovation Center for Genomics (ICG), Peking University, Beijing, China
| | - Chengsong Sun
- Shanghai Institute of Infectious Disease and Biosecurity, State Key Laboratory of Genetic Engineering, Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, Ministry of Education Key Laboratory of Contemporary Anthropology, School of Life Science, Fudan University, Shanghai, China
| | - Bingkuan Zhu
- Shanghai Institute of Infectious Disease and Biosecurity, State Key Laboratory of Genetic Engineering, Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, Ministry of Education Key Laboratory of Contemporary Anthropology, School of Life Science, Fudan University, Shanghai, China
| | - Wei Zhang
- Shanghai Institute of Infectious Disease and Biosecurity, State Key Laboratory of Genetic Engineering, Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, Ministry of Education Key Laboratory of Contemporary Anthropology, School of Life Science, Fudan University, Shanghai, China
| | - Cun Yi
- Shanghai Institute of Infectious Disease and Biosecurity, State Key Laboratory of Genetic Engineering, Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, Ministry of Education Key Laboratory of Contemporary Anthropology, School of Life Science, Fudan University, Shanghai, China
| | - Zhidan Li
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Key Laboratory of Parasite and Vector Biology of China Ministry of Health, WHO Collaborating Centre for Tropical Diseases, Joint Research Laboratory of Genetics and Ecology on Parasite-host Interaction, Chinese Center for Disease Control and Prevention and Fudan University, Shanghai, China
| | - Jipeng Wang
- Shanghai Institute of Infectious Disease and Biosecurity, State Key Laboratory of Genetic Engineering, Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, Ministry of Education Key Laboratory of Contemporary Anthropology, School of Life Science, Fudan University, Shanghai, China
| | - Bin Xu
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Key Laboratory of Parasite and Vector Biology of China Ministry of Health, WHO Collaborating Centre for Tropical Diseases, Joint Research Laboratory of Genetics and Ecology on Parasite-host Interaction, Chinese Center for Disease Control and Prevention and Fudan University, Shanghai, China
| | - Zheng Feng
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Key Laboratory of Parasite and Vector Biology of China Ministry of Health, WHO Collaborating Centre for Tropical Diseases, Joint Research Laboratory of Genetics and Ecology on Parasite-host Interaction, Chinese Center for Disease Control and Prevention and Fudan University, Shanghai, China
| | - Yangyi Huang
- Biomedical Pioneering Innovation Center (BIOPIC) and Beijing Advanced Innovation Center for Genomics (ICG), Peking University, Beijing, China; College of Chemistry and Molecular Engineering, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, China
| | - Yan Lu
- Shanghai Institute of Infectious Disease and Biosecurity, State Key Laboratory of Genetic Engineering, Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, Ministry of Education Key Laboratory of Contemporary Anthropology, School of Life Science, Fudan University, Shanghai, China.
| | - Wei Hu
- Shanghai Institute of Infectious Disease and Biosecurity, State Key Laboratory of Genetic Engineering, Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, Ministry of Education Key Laboratory of Contemporary Anthropology, School of Life Science, Fudan University, Shanghai, China; National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Key Laboratory of Parasite and Vector Biology of China Ministry of Health, WHO Collaborating Centre for Tropical Diseases, Joint Research Laboratory of Genetics and Ecology on Parasite-host Interaction, Chinese Center for Disease Control and Prevention and Fudan University, Shanghai, China; College of Life Sciences, Inner Mongolia University, Hohhot, China.
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Solovyeva A, Levakin I, Zorin E, Adonin L, Khotimchenko Y, Podgornaya O. Transposons-Based Clonal Diversity in Trematode Involves Parts of CR1 (LINE) in Eu- and Heterochromatin. Genes (Basel) 2021; 12:1129. [PMID: 34440303 PMCID: PMC8392823 DOI: 10.3390/genes12081129] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 07/22/2021] [Accepted: 07/23/2021] [Indexed: 01/21/2023] Open
Abstract
Trematode parthenitae have long been believed to form clonal populations, but clonal diversity has been discovered in this asexual stage of the lifecycle. Clonal polymorphism in the model species Himasthla elongata has been previously described, but the source of this phenomenon remains unknown. In this work, we traced cercarial clonal diversity using a simplified amplified fragment length polymorphism (SAFLP) method and characterised the nature of fragments in diverse electrophoretic bands. The repetitive elements were identified in both the primary sequence of the H. elongata genome and in the transcriptome data. Long-interspersed nuclear elements (LINEs) and long terminal repeat retrotransposons (LTRs) were found to represent an overwhelming majority of the genome and the transposon transcripts. Most sequenced fragments from SAFLP pattern contained the reverse transcriptase (RT, ORF2) domains of LINEs, and only a few sequences belonged to ORFs of LTRs and ORF1 of LINEs. A fragment corresponding to a CR1-like (LINE) spacer region was discovered and named CR1-renegade (CR1-rng). In addition to RT-containing CR1 transcripts, we found short CR1-rng transcripts in the redia transcriptome and short contigs in the mobilome. Probes against CR1-RT and CR1-rng presented strikingly different pictures in FISH mapping, despite both being fragments of CR1. In silico data and Southern blotting indicated that CR1-rng is not tandemly organised. CR1 involvement in clonal diversity is discussed.
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Affiliation(s)
- Anna Solovyeva
- Institute of Cytology of the Russian Academy of Science, Tikhoretsky Ave 4, 194064 Saint Petersburg, Russia;
- Zoological Institute of the Russian Academy of Sciences, Universitetskaya Nab 1, 199034 Saint Petersburg, Russia;
| | - Ivan Levakin
- Zoological Institute of the Russian Academy of Sciences, Universitetskaya Nab 1, 199034 Saint Petersburg, Russia;
| | - Evgeny Zorin
- All-Russia Research Institute for Agricultural Microbiology, Pushkin 8, 196608 Saint Petersburg, Russia;
| | - Leonid Adonin
- Moscow Institute of Physics and Technology, Institutskiy per 9, 141701 Dolgoprudny, Russia;
| | - Yuri Khotimchenko
- School of Biomedicine, Far Eastern Federal University, Sukhanova St 8, 690091 Vladivostok, Russia;
| | - Olga Podgornaya
- Institute of Cytology of the Russian Academy of Science, Tikhoretsky Ave 4, 194064 Saint Petersburg, Russia;
- Department of Cytology and Histology, Saint Petersburg State University, Universitetskaya Nab 7/9, 199034 Saint Petersburg, Russia
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5
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Gu MJ, Li YW, Emery AM, Li SZ, Jiang YZ, Dong HF, Zhao QP. The genetic variation of different developmental stages of Schistosoma japonicum: do the distribution in snails and pairing preference benefit the transmission? Parasit Vectors 2020; 13:360. [PMID: 32690109 PMCID: PMC7372819 DOI: 10.1186/s13071-020-04240-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Accepted: 07/15/2020] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Schistosoma japonicum is a waterborne parasite that causes schistosomiasis in humans and in more than 40 animal species. Schistosoma japonicum shows distinct genetic differentiation among geographical populations and multiple hosts, but the genetic diversity of different developmental stages of S. japonicum from is less studied. Such studies could elucidate ecological mechanisms in disease transmission by analysing feedbacks in individual physiology and population state. METHODS After infection using cercariae from a pool of snails shedding together (Method I) and infection using mixed equal numbers of cercariae from individually shed snails (Method II), different developmental stages of S. japonicum were genotyped with microsatellite loci, including 346 cercariae, 701 adult worms and 393 miracidia. Genetic diversity and molecular variation were calculated at different population levels. Kinships (I') among cercariae at intra-snail and inter-snail levels were evaluated. Genetic distance (Dsw) was compared between paired and unpaired worms, and partner changing was investigated through paternity identification for miracidia. RESULTS The cercaria clones in individual snails varied from 1 to 8 and the kinship of cercariae within individual snails was significant higher (P < 0.001) than that among different snails after deleting near-identical multi-locus genotypes (niMLGs). The allelic diversity of worms in Method I was lower (P < 0.001) than that in Method II, and allele frequency among mice in Method I was also less consistent. The parents of some miracidia were worms that were not paired when collected. The Dsw between each female of paired and unpaired males was much larger (P < 0.001) than that between the female and male in each pair. CONCLUSIONS Most of the infected snails contained multiple miracidia clones. The aggregation of genetically similar S. japonicum miracidia in individual snails and the unbalanced distribution of miracidia among snails suggests a non-uniform genetic distribution of cercariae among snails in the field. This further influenced the genetic structure of adult worms from infections with different cercariae sampling methods. Schistosoma japonicum in mice can change paired partner, preferring to mate with genetically similar worms. These characteristics provide implications for understanding the balance in genetic diversity of S. japonicum related to the transmission of schistosomiasis.
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Affiliation(s)
- Meng-Jie Gu
- Department of Parasitology, School of Basic Medical Sciences, Wuhan University, Wuhan, 430071 Hubei China
| | - Yan-Wei Li
- Department of Parasitology, School of Basic Medical Sciences, Wuhan University, Wuhan, 430071 Hubei China
- Hubei Provincial Center for Disease Control and Prevention, Wuhan, 430072 Hubei China
| | - Aidan M. Emery
- Department of Life Sciences, Natural History Museum, Cromwell Road, London, SW7 5BD UK
| | - Shi-Zhu Li
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, National Center for Tropical Diseases Research, WHO Collaborating Center for Tropical Diseases, Key Laboratory of Parasite and Vector Biology, Ministry of Health, Shanghai, 200025 China
| | - Yong-Zhong Jiang
- Hubei Provincial Center for Disease Control and Prevention, Wuhan, 430072 Hubei China
| | - Hui-Fen Dong
- Department of Parasitology, School of Basic Medical Sciences, Wuhan University, Wuhan, 430071 Hubei China
| | - Qin-Ping Zhao
- Department of Parasitology, School of Basic Medical Sciences, Wuhan University, Wuhan, 430071 Hubei China
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6
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Pennance T, Allan F, Emery A, Rabone M, Cable J, Garba AD, Hamidou AA, Webster JP, Rollinson D, Webster BL. Interactions between Schistosoma haematobium group species and their Bulinus spp. intermediate hosts along the Niger River Valley. Parasit Vectors 2020; 13:268. [PMID: 32448268 PMCID: PMC7247258 DOI: 10.1186/s13071-020-04136-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Accepted: 05/14/2020] [Indexed: 01/09/2023] Open
Abstract
Background Urogenital schistosomiasis, caused by infection with Schistosoma haematobium, is endemic in Niger but complicated by the presence of Schistosoma bovis, Schistosoma curassoni and S. haematobium group hybrids along with various Bulinus snail intermediate host species. Establishing the schistosomes and snails involved in transmission aids disease surveillance whilst providing insights into snail-schistosome interactions/compatibilities and biology. Methods Infected Bulinus spp. were collected from 16 villages north and south of the Niamey region, Niger, between 2011 and 2015. From each Bulinus spp., 20–52 cercariae shed were analysed using microsatellite markers and a subset identified using the mitochondrial (mt) cox1 and nuclear ITS1 + 2 and 18S DNA regions. Infected Bulinus spp. were identified using both morphological and molecular analysis (partial mt cox1 region). Results A total of 87 infected Bulinus from 24 sites were found, 29 were molecularly confirmed as B. truncatus, three as B. forskalii and four as B. globosus. The remaining samples were morphologically identified as B. truncatus (n = 49) and B. forskalii (n = 2). The microsatellite analysis of 1124 cercariae revealed 186 cercarial multilocus genotypes (MLGs). Identical cercarial genotypes were frequently (60%) identified from the same snail (clonal populations from a single miracidia); however, several (40%) of the snails had cercariae of different genotypes (2–10 MLG’s) indicating multiple miracidial infections. Fifty-seven of the B. truncatus and all of the B. forskalii and B. globosus were shedding the Bovid schistosome S. bovis. The other B. truncatus were shedding the human schistosomes, S. haematobium (n = 6) and the S. haematobium group hybrids (n = 13). Two B. truncatus had co-infections with S. haematobium and S. haematobium group hybrids whilst no co-infections with S. bovis were observed. Conclusions This study has advanced our understanding of human and bovid schistosomiasis transmission in the Niger River Valley region. Human Schistosoma species/forms (S. haematobium and S. haematobium hybrids) were found transmitted only in five villages whereas those causing veterinary schistosomiasis (S. bovis), were found in most villages. Bulinus truncatus was most abundant, transmitting all Schistosoma species, while the less abundant B. forskalii and B. globosus, only transmitted S. bovis. Our data suggest that species-specific biological traits may exist in relation to co-infections, snail-schistosome compatibility and intramolluscan schistosome development. ![]()
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Affiliation(s)
- Tom Pennance
- Department of Life Sciences, Natural History Museum, Cromwell Road, South Kensington, London, SW7 5BD, UK. .,School of Biosciences, Cardiff University, Cardiff, CF10 3AX, UK. .,London Centre for Neglected Tropical Disease Research, Imperial College London, School of Public Health, Norfolk Pl, Paddington, London, W2 1PG, UK.
| | - Fiona Allan
- Department of Life Sciences, Natural History Museum, Cromwell Road, South Kensington, London, SW7 5BD, UK.,London Centre for Neglected Tropical Disease Research, Imperial College London, School of Public Health, Norfolk Pl, Paddington, London, W2 1PG, UK
| | - Aidan Emery
- Department of Life Sciences, Natural History Museum, Cromwell Road, South Kensington, London, SW7 5BD, UK.,London Centre for Neglected Tropical Disease Research, Imperial College London, School of Public Health, Norfolk Pl, Paddington, London, W2 1PG, UK
| | - Muriel Rabone
- Department of Life Sciences, Natural History Museum, Cromwell Road, South Kensington, London, SW7 5BD, UK.,London Centre for Neglected Tropical Disease Research, Imperial College London, School of Public Health, Norfolk Pl, Paddington, London, W2 1PG, UK
| | - Jo Cable
- School of Biosciences, Cardiff University, Cardiff, CF10 3AX, UK
| | - Amadou Djirmay Garba
- Réseau International Schistosomoses, Environnement, Aménagement et Lutte (RISEAL-Niger), 333, Avenue des Zarmakoye, B.P. 13724, Niamey, Niger.,World Health Organization, Geneva, Switzerland
| | - Amina Amadou Hamidou
- Réseau International Schistosomoses, Environnement, Aménagement et Lutte (RISEAL-Niger), 333, Avenue des Zarmakoye, B.P. 13724, Niamey, Niger
| | - Joanne P Webster
- London Centre for Neglected Tropical Disease Research, Imperial College London, School of Public Health, Norfolk Pl, Paddington, London, W2 1PG, UK.,Department of Pathology and Pathogen Biology, Centre for Emerging, Endemic and Exotic Diseases (CEEED), Royal Veterinary College, University of London, Hertfordshire, AL9 7TA, UK
| | - David Rollinson
- Department of Life Sciences, Natural History Museum, Cromwell Road, South Kensington, London, SW7 5BD, UK.,London Centre for Neglected Tropical Disease Research, Imperial College London, School of Public Health, Norfolk Pl, Paddington, London, W2 1PG, UK
| | - Bonnie L Webster
- Department of Life Sciences, Natural History Museum, Cromwell Road, South Kensington, London, SW7 5BD, UK. .,London Centre for Neglected Tropical Disease Research, Imperial College London, School of Public Health, Norfolk Pl, Paddington, London, W2 1PG, UK.
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7
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Hodgkinson JE, Cwiklinski K, Beesley N, Hartley C, Allen K, Williams DJL. Clonal amplification of Fasciola hepatica in Galba truncatula: within and between isolate variation of triclabendazole-susceptible and -resistant clones. Parasit Vectors 2018; 11:363. [PMID: 29941045 PMCID: PMC6020221 DOI: 10.1186/s13071-018-2952-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Accepted: 06/13/2018] [Indexed: 11/10/2022] Open
Abstract
Background Fasciola hepatica is of worldwide significance, impacting on the health, welfare and productivity of livestock and regarded by WHO as a re-emerging zoonosis. Triclabendazole (TCBZ), the drug of choice for controlling acute fasciolosis in livestock, is also the drug used to treat human infections. However TCBZ-resistance is now considered a major threat to the effective control of F. hepatica. It has yet to be demonstrated whether F. hepatica undergoes a genetic clonal expansion in the snail intermediate host, Galba truncatula, and to what extent amplification of genotypes within the snail facilitates accumulation of drug resistant parasites. Little is known about genotypic and phenotypic variation within and between F. hepatica isolates. Results Six clonal isolates of F. hepatica (3× triclabendazole-resistant, TCBZ-R and 3× triclabendazole-susceptible, TCBZ-S) were generated. Snails infected with one miracidium started to shed cercariae 42–56 days post-infection and shed repeatedly up to a maximum of 11 times. A maximum of 884 cercariae were shed by one clonally-infected snail (FhLivS1) at a single time point, with > 3000 clonal metacercariae shed over its lifetime. Following experimental infection all 12 sheep were FEC positive at the time of TCBZ treatment. Sheep infected with one of three putative TCBZ-S clones and treated with TCBZ had no parasites in the liver at post-mortem, whilst sheep each infected with putative TCBZ-R isolates had 35–165 adult fluke at post-mortem, despite TCBZ treatment. All six untreated control animals had between 15–127 parasites. A single multi-locus genotype was reported for every fluke from each of the six clonal isolates. Adult F. hepatica showed considerable variation in weight, ranging from 20–280 mg, with variation in weight evident within and amongst clonal isolates. Conclusions A genetic clonal expansion occurs within G. truncatula, highlighting the potential for amplification of drug resistant genotypes of F. hepatica. Variation in the weight of parasites within and between clonal isolates and when comparing isolates that are either susceptible or resistant to TCBZ represent inherent variation in liver fluke and cannot be attributed to their resistance or susceptibility traits.
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Affiliation(s)
- Jane E Hodgkinson
- Veterinary Parasitology, Dept Infection Biology, Institute of Infection and Global Health, University of Liverpool, Liverpool, L69 7ZJ, UK.
| | - Krystyna Cwiklinski
- Veterinary Parasitology, Dept Infection Biology, Institute of Infection and Global Health, University of Liverpool, Liverpool, L69 7ZJ, UK.,School of Biological Sciences, Medical Biology Centre, Queen's University Belfast, Belfast, BT9 7BL, UK
| | - Nicola Beesley
- Veterinary Parasitology, Dept Infection Biology, Institute of Infection and Global Health, University of Liverpool, Liverpool, L69 7ZJ, UK
| | - Catherine Hartley
- Veterinary Parasitology, Dept Infection Biology, Institute of Infection and Global Health, University of Liverpool, Liverpool, L69 7ZJ, UK
| | - Katherine Allen
- Veterinary Parasitology, Dept Infection Biology, Institute of Infection and Global Health, University of Liverpool, Liverpool, L69 7ZJ, UK
| | - Diana J L Williams
- Veterinary Parasitology, Dept Infection Biology, Institute of Infection and Global Health, University of Liverpool, Liverpool, L69 7ZJ, UK
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8
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Moendeg KJ, Angeles JMM, Nakao R, Leonardo LR, Fontanilla IKC, Goto Y, Kirinoki M, Villacorte EA, Rivera PT, Inoue N, Chigusa Y, Kawazu SI. Geographic strain differentiation of Schistosoma japonicum in the Philippines using microsatellite markers. PLoS Negl Trop Dis 2017; 11:e0005749. [PMID: 28692692 PMCID: PMC5519200 DOI: 10.1371/journal.pntd.0005749] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Revised: 07/20/2017] [Accepted: 06/25/2017] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Microsatellites have been found to be useful in determining genetic diversities of various medically-important parasites which can be used as basis for an effective disease management and control program. In Asia and Africa, the identification of different geographical strains of Schistosoma japonicum, S. haematobium and S. mansoni as determined through microsatellites could pave the way for a better understanding of the transmission epidemiology of the parasite. Thus, the present study aims to apply microsatellite markers in analyzing the populations of S. japonicum from different endemic areas in the Philippines for possible strain differentiation. METHODOLOGY/ PRINCIPAL FINDINGS Experimental mice were infected using the cercariae of S. japonicum collected from infected Oncomelania hupensis quadrasi snails in seven endemic municipalities. Adult worms were harvested from infected mice after 45 days of infection and their DNA analyzed against ten previously characterized microsatellite loci. High genetic diversity was observed in areas with high endemicity. The degree of genetic differentiation of the parasite population between endemic areas varies. Geographical separation was considered as one of the factors accounting for the observed difference between populations. Two subgroups have been observed in one of the study sites, suggesting that co-infection with several genotypes of the parasite might be present in the population. Clustering analysis showed no particular spatial structuring between parasite populations from different endemic areas. This result could possibly suggest varying degrees of effects of the ongoing control programs and the existing gene flow in the populations, which might be attributed to migration and active movement of infected hosts from one endemic area to another. CONCLUSIONS/ SIGNIFICANCE Based on the results of the study, it is reasonable to conclude that genetic diversity could be one possible criterion to assess the infection status in highly endemic areas. Genetic surveillance using microsatellites is therefore important to predict the ongoing gene flow and degree of genetic diversity, which indirectly reflects the success of the control program in schistosomiasis-endemic areas.
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Affiliation(s)
- Kharleezelle J. Moendeg
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido, Japan
- Department of Biology, School of Science and Engineering, Ateneo de Manila University, Quezon City, Manila, Philippines
| | - Jose Ma M. Angeles
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido, Japan
| | - Ryo Nakao
- Laboratory of Parasitology, Department of Disease Control, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Lydia R. Leonardo
- Department of Parasitology, College of Public Health, University of the Philippines Manila, Philippines
| | | | - Yasuyuki Goto
- Laboratory of Molecular Immunology, Department of Animal Resource Sciences, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Masashi Kirinoki
- Department of Tropical Medicine and Parasitology, Dokkyo Medical University School of Medicine, Tochigi, Japan
| | - Elena A. Villacorte
- Department of Parasitology, College of Public Health, University of the Philippines Manila, Philippines
| | - Pilarita T. Rivera
- Department of Parasitology, College of Public Health, University of the Philippines Manila, Philippines
| | - Noboru Inoue
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido, Japan
| | - Yuichi Chigusa
- Department of Tropical Medicine and Parasitology, Dokkyo Medical University School of Medicine, Tochigi, Japan
| | - Shin-ichiro Kawazu
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido, Japan
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9
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An updated look at the uneven distribution of cryptic diversity among parasitic helminths. J Helminthol 2017; 92:197-202. [PMID: 28260533 DOI: 10.1017/s0022149x17000189] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Cryptic parasite diversity is a major issue for taxonomy and systematics, and for attempts to control diseases of humans, domestic animals and wildlife. Here, we re-examine an earlier report that, after correcting for sampling effort, more cryptic species of trematodes are found per published study than for other helminth taxa. We performed a meta-analysis of 110 studies that used DNA sequences to search for cryptic species in parasitic helminth taxa. After correcting for study effort and accounting for the biogeographical region of origins, we found that more cryptic species tend to be uncovered among trematodes, and fewer among cestodes and animal-parasitic nematodes, than in other helminth groups. However, this pattern was only apparent when we included only studies using nuclear markers in the analysis; it was not seen in a separate analysis based only on mitochondrial markers. We propose that the greater occurrence of cryptic diversity among trematodes may be due to some of their unique features, such as their mode of reproduction or frequent lack of hard morphological structures, or to the way in which trematode species are described. Whatever the reason, the high frequency of cryptic species among trematodes has huge implications for estimates of parasite diversity and for future taxonomic research.
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Li Y, Yin M, Wu Q, McManus DP, Blair D, Li H, Xu B, Mo X, Feng Z, Hu W. Genetic diversity and selection of three nuclear genes in Schistosoma japonicum populations. Parasit Vectors 2017; 10:87. [PMID: 28212676 PMCID: PMC5316221 DOI: 10.1186/s13071-017-2033-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2016] [Accepted: 02/11/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The blood fluke, Schistosoma japonicum still causes severe disease in China, the Philippines and Indonesia. Although there have been some studies the molecular epidemiology of this persistent and harmful parasite, few have explored the possibility and implications of selection in S. japonicum populations. METHODS We analyzed diversity and looked for evidence of selection at three nuclear genes (SjIpp2, SjFabp and SjT22.6) in 13 S. japonicum populations. RESULTS SjT22.6 was found to exhibit high nucleotide diversity and was under positive selection in the mountainous region of mainland China. As a tegumental protein, its secondary and tertiary structure differed between S. japonicum strains from the mountainous and lakes regions. In contrast, SjIpp2 and SjFabp had relatively low levels of nucleotide diversity and did not show significant departure from neutrality. CONCLUSIONS As a tegument-associated antigen-encoding gene of S. japonicum, SjT22.6 has high nucleotide diversity and appears to be under positive selection in the mountainous region of mainland China.
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Affiliation(s)
- Yaqi Li
- School of Life Science, Fudan University, Songhu Road 2005, Shanghai, China
| | - Mingbo Yin
- School of Life Science, Fudan University, Songhu Road 2005, Shanghai, China
- MOE Key Laboratory for Biodiversity Science and Ecological Engineering, School of Life Science, Fudan University, Songhu Road 2005, Shanghai, China
| | - Qunfeng Wu
- School of Life Science, Fudan University, Songhu Road 2005, Shanghai, China
| | - Donald P. McManus
- QIMR Berghofer Medical Research Institute, 300 Herston Road, Brisbane, QLD 4029 Australia
| | - David Blair
- College of Science and Engineering, James Cook University, Townsville, QLD 4811 Australia
| | - Hongyan Li
- School of Life Science, Fudan University, Songhu Road 2005, Shanghai, China
| | - Bin Xu
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, 207 Rui Jin Er Road, Shanghai, 200025 China
| | - Xiaojin Mo
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, 207 Rui Jin Er Road, Shanghai, 200025 China
| | - Zheng Feng
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, 207 Rui Jin Er Road, Shanghai, 200025 China
| | - Wei Hu
- School of Life Science, Fudan University, Songhu Road 2005, Shanghai, China
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, 207 Rui Jin Er Road, Shanghai, 200025 China
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Genetic diversity and structure of Schistosoma japonicum within two marshland villages of Anhui, China, prior to schistosome transmission control and elimination. Parasitol Res 2016; 116:569-576. [PMID: 27838835 DOI: 10.1007/s00436-016-5321-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Accepted: 11/04/2016] [Indexed: 12/27/2022]
Abstract
Schistosomiasis is caused by the genus Schistosoma and affected more than 250 million people worldwide. Schistosoma japonicum was once seriously endemic in China and nearly 60 years of efforts has seen great success in disease control. However, due to its zoonotic nature and complex life cycle, the schistosomiasis transmission control and final elimination would require, besides an intersectoral approach, deep understanding of population genetics of the parasite. We therefore performed a snail survey in two marshland villages of Anhui province of China and collected S. japonicum cercariae from infected snails. By using the recent developed microsatellite panel comprising seven loci, we genotyped the sampled parasites and analyzed the population genetic diversity and structure. The results showed much lower infection prevalence of S. japonicum in snails and low infected snail density in either marshland village. Through population genetic analyses, a considerable genetic diversity of parasites was revealed, whereas a small number of clusters were inferred and the sign of bottleneck effect was detected in each village. For the first time in S. japonicum in two villages, we provided estimates of effective population sizes with two different approaches. The results indicated that the parasite in two villages could eventually be eradicated with the ongoing integral control measures, but with potential risk of reinvasion of immigrant parasites through the Yangtze River. Such would be of great importance in assessment of the effects of ongoing control measures and prediction of the transmission capability for S. japonicum, thus guiding decisions on the choice of further control work.
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Yin M, Liu X, Xu B, Huang J, Zheng Q, Yang Z, Feng Z, Han ZG, Hu W. Genetic variation between Schistosoma japonicum lineages from lake and mountainous regions in China revealed by resequencing whole genomes. Acta Trop 2016; 161:79-85. [PMID: 27207135 DOI: 10.1016/j.actatropica.2016.05.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2015] [Revised: 04/25/2016] [Accepted: 05/16/2016] [Indexed: 02/08/2023]
Abstract
Schistosoma infection is a major cause of morbidity and mortality worldwide. Schistosomiasis japonica is endemic in mainland China along the Yangtze River, typically distributed in two geographical categories of lake and mountainous regions. Study on schistosome genetic diversity is of interest in respect of understanding parasite biology and transmission, and formulating control strategy. Certain genetic variations may be associated with adaptations to different ecological habitats. The aim of this study is to gain insight into Schistosoma japonicum genetic variation, evolutionary origin and associated causes of different geographic lineages through examining homozygous Single Nucleotide Polymorphisms (SNPs) based on resequenced genome data. We collected S. japonicum samples from four sites, three in the lake regions (LR) of mid-east (Guichi and Tonglin in Anhui province, Laogang in Hunan province) and one in mountainous region (MR) (Xichang in Sichuan province) of south-west of China, resequenced their genomes using Next Generation Sequencing (NGS) technology, and made use of the available database of S. japonicum draft genomic sequence as a reference in genome mapping. A total of 14,575 SNPs from 2059 genes were identified in the four lineages. Phylogenetic analysis confirmed significant genetic variation exhibited between the different geographical lineages, and further revealed that the MR Xichang lineage is phylogenetically closer to LR Guich lineage than to other two LR lineages, and the MR lineage might be evolved from LR lineages. More than two thirds of detected SNPs were nonsynonymous; functional annotation of the SNP-containing genes showed that they are involved mainly in biological processes such as signaling and response to stimuli. Notably, unique nonsynonymous SNP variations were detected in 66 genes of MR lineage, inferring possible genetic adaption to mountainous ecological condition.
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Huo GN, Liu L, He HB, Attwood SW. An investigation into the potential effects of infrapopulation structure and other sources of sampling error, on population genetic studies of the transmission of Schistosoma japonicum (Trematoda: Digenea). Parasit Vectors 2016; 9:165. [PMID: 27000844 PMCID: PMC4802887 DOI: 10.1186/s13071-016-1454-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Accepted: 03/15/2016] [Indexed: 02/05/2023] Open
Abstract
Background Schistosoma japonicum remains a major challenge to human and animal health. Earlier microsatellite-based studies reported possible definitive-host-specific private alleles within S. japonicum, opening the possibility that different definitive hosts might harbour different parasite strains. Previous investigations have also detected near-identical multilocus genotypes in populations of adult worms - possibly the result of mutations occurring during the asexual (intramolluscan) phase of clonal expansion. Research has also revealed extensive deviations from Hardy-Weinberg Proportions (HWP) and conflicting results among studies. The present study was performed to examine some of the potential effects of infrapopulation structure on microsatellite-based studies of the transmission ecology of S. japonicum. Potential sources of bias considered included organotropic distribution of worms, non-random mating and corrections for clonal expansion. Results Stool samples from naturally infected hosts were used to infect snails in the laboratory and thereby expose mice. 274 individual worms were typed at seven microsatellite loci. Removal of individuals bearing duplicate MLGs (as a correction for presumed clonal expansion) had an impact on both HWP and organotropic genetic differentiation. The study found no evidence that heterozygote deficiencies were caused by a Wahlund effect. Female-male pairings appeared to be random and there was no evidence for mate choice by heterozygosity. There was some indication that excess heterozygosity, induced by clonal expansion, can offset heterozygote deficiencies caused by small population size or populations fragmented by parasite control efforts. Conclusions The view is supported that miracidia are preferable to adult worms in investigations into host-specific parasite lineages. Where adults must be used, extreme care should be taken with regard to sampling if infrapopulations of small animals are compared with those of larger animals; this is because of organotropic patterns in genetic variation and the tendency to sample from different organs in differently sized hosts. As corrections for clones may accentuate signals of population subdivision, corrections should only be made if tests for clonal expansion prove positive. Finally, evidence for heterozygote deficiency caused by small sample size, calls for carefully designed random and comprehensive sampling strategies for S. japonicum in China, where control efforts have greatly fragmented parasite populations. Electronic supplementary material The online version of this article (doi:10.1186/s13071-016-1454-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Guan-Nan Huo
- State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Chengdu, People's Republic of China
| | - Liang Liu
- State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Chengdu, People's Republic of China
| | - Hong-Bin He
- Hunan Institute of Parasitic Diseases, Yueyang, Hunan, People's Republic of China
| | - Stephen W Attwood
- State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Chengdu, People's Republic of China. .,Department of Life Sciences, The Natural History Museum, London, UK.
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Yin M, Li H, Blair D, Xu B, Feng Z, Hu W. Temporal genetic diversity of Schistosoma japonicum in two endemic sites in China revealed by microsatellite markers. Parasit Vectors 2016; 9:36. [PMID: 26800884 PMCID: PMC4724141 DOI: 10.1186/s13071-016-1326-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Accepted: 01/19/2016] [Indexed: 11/21/2022] Open
Abstract
BACKGROUND Schistosomiasis is one of the neglected tropical diseases. The causative agent of schistosomiasis in China, Schistosoma japonicum, has long been a major public health problem. An understanding of fundamental evolutionary and genetic processes in this species has major implications for its control and elimination. Intensive control efforts have greatly reduced the incidence of schistosomiasis in China, but little is known about the genetic consequences of these efforts. METHODS To investigate this, we sampled twice (years 2003 and 2011) from two endemic regions where populations of S. japonicum had persisted despite control efforts and genotyped these samples using ten microsatellite markers. Our main hypothesis was that parasite genetic diversity would be greatly reduced across this time period. CONCLUSIONS There was no apparent reduction in allelic diversity, and a non-significant reduction in clonal diversity in these parasite populations between 2003 and 2011. We did, however, detect temporal genetic differentiation among the samples. Such a significant temporal genetic variation of S. japonicum populations has not been reported before.
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Affiliation(s)
- Mingbo Yin
- School of Life Sciences, Fudan University, 2005 Songhu Road, Shanghai, 200438, China.
| | - Hongyan Li
- School of Life Sciences, Fudan University, 2005 Songhu Road, Shanghai, 200438, China.
| | - David Blair
- College of Marine and Environmental Sciences, James Cook University, Townsville, Qld 4811, Australia.
| | - Bin Xu
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, 207 Ruijin Er Road, Shanghai, 200025, China.
| | - Zheng Feng
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, 207 Ruijin Er Road, Shanghai, 200025, China.
| | - Wei Hu
- School of Life Sciences, Fudan University, 2005 Songhu Road, Shanghai, 200438, China.
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, 207 Ruijin Er Road, Shanghai, 200025, China.
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Yin M, Zheng HX, Su J, Feng Z, McManus DP, Zhou XN, Jin L, Hu W. Co-dispersal of the blood fluke Schistosoma japonicum and Homo sapiens in the Neolithic Age. Sci Rep 2015; 5:18058. [PMID: 26686813 PMCID: PMC4685303 DOI: 10.1038/srep18058] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2015] [Accepted: 11/03/2015] [Indexed: 11/09/2022] Open
Abstract
The global spread of human infectious diseases is of considerable public health and biomedical interest. Little is known about the relationship between the distribution of ancient parasites and that of their human hosts. Schistosoma japonicum is one of the three major species of schistosome blood flukes causing the disease of schistosomiasis in humans. The parasite is prevalent in East and Southeast Asia, including the People's Republic of China, the Philippines and Indonesia. We studied the co-expansion of S. japonicum and its human definitive host. Phylogenetic reconstruction based on complete mitochondrial genome sequences showed that S. japonicum radiated from the middle and lower reaches of the Yangtze River to the mountainous areas of China, Japan and Southeast Asia. In addition, the parasite experienced two population expansions during the Neolithic agriculture era, coinciding with human migration and population growth. The data indicate that the advent of rice planting likely played a key role in the spread of schistosomiasis in Asia. Moreover, the presence of different subspecies of Oncomelania hupensis intermediate host snails in different localities in Asia allowed S. japonicum to survive in new rice-planting areas, and concurrently drove the intraspecies divergence of the parasite.
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Affiliation(s)
- Mingbo Yin
- State Key Laboratory of Genetic Engineering and Ministry of Education Key Laboratory of Contemporary Anthropology, Collaborative Innovation Center of Genetics and Development, School of Life Sciences, Fudan University, Shanghai, 200438, China
| | - Hong-Xiang Zheng
- State Key Laboratory of Genetic Engineering and Ministry of Education Key Laboratory of Contemporary Anthropology, Collaborative Innovation Center of Genetics and Development, School of Life Sciences, Fudan University, Shanghai, 200438, China
| | - Jing Su
- State Key Laboratory of Genetic Engineering and Ministry of Education Key Laboratory of Contemporary Anthropology, Collaborative Innovation Center of Genetics and Development, School of Life Sciences, Fudan University, Shanghai, 200438, China
| | - Zheng Feng
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Key Laboratory of Parasite and Vector Biology of the Chinese Ministry of Health, WHO Collaborating Center for Malaria, Schistosomiasis and Filariasis, Shanghai, 200025, China
| | - Donald P. McManus
- QIMR Berghofer Medical Research Institute, Brisbane, Queensland 4006, Australia
| | - Xiao-Nong Zhou
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Key Laboratory of Parasite and Vector Biology of the Chinese Ministry of Health, WHO Collaborating Center for Malaria, Schistosomiasis and Filariasis, Shanghai, 200025, China
| | - Li Jin
- State Key Laboratory of Genetic Engineering and Ministry of Education Key Laboratory of Contemporary Anthropology, Collaborative Innovation Center of Genetics and Development, School of Life Sciences, Fudan University, Shanghai, 200438, China
- Chinese Academy of Sciences Key Laboratory of Computational Biology, CAS-MPG Partner Institute for Computational Biology, SIBS, CAS, Shanghai, 200021, China
| | - Wei Hu
- State Key Laboratory of Genetic Engineering and Ministry of Education Key Laboratory of Contemporary Anthropology, Collaborative Innovation Center of Genetics and Development, School of Life Sciences, Fudan University, Shanghai, 200438, China
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Key Laboratory of Parasite and Vector Biology of the Chinese Ministry of Health, WHO Collaborating Center for Malaria, Schistosomiasis and Filariasis, Shanghai, 200025, China
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16
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Gao YM, Lu DB, Ding H, Lamberton PHL. Detecting genotyping errors at Schistosoma japonicum microsatellites with pedigree information. Parasit Vectors 2015; 8:452. [PMID: 26350750 PMCID: PMC4563838 DOI: 10.1186/s13071-015-1074-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Accepted: 09/04/2015] [Indexed: 11/11/2022] Open
Abstract
BACKGROUND Schistosomiasis japonica remains a major public health problem in China. Integrating molecular analyses, such as population genetic analyses, of the parasite into the on-going surveillance programs is helpful in exploring the factors causing the persistence and/or spread of Schistosoma japonicum. However, genotyping errors can seriously affect the results of such studies, unless accounted for in the analyses. METHODS We assessed the genotyping errors (missing alleles or false alleles) of seven S. japonicum microsatellites, using a pedigree data approach for schistosome miracidia, which were stored on Whatman FTA cards. RESULTS Among 107 schistosome miracidia successfully genotyped, resulting in a total of 715 loci calls, a total of 31 genotyping errors were observed with 25.2% of the miracidia having at least one error. The error rate per locus differed among loci, which ranged from 0 to 9.8%, with the mean error rate 4.3% over loci. With the parentage analysis software Cervus, the assignment power with these seven markers was estimated to be 89.5% for one parent and 99.9% for a parent pair. One locus was inferred to have a high number of null alleles and a second with a high mistyping rate. CONCLUSION To the authors' knowledge, this is the first time that S. japonicum pedigrees have been used in an assessment of genotyping errors of microsatellite markers. The observed locus-specific error rate will benefit downstream epidemiological or ecological analyses of S. japonicum with the markers.
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Affiliation(s)
- Yu-Meng Gao
- Department of Epidemiology and Statistics, School of Public Health, Soochow University, Suzhou, 215123, China.
- Jiangsu Key Laboratory of Preventive and Translational Medicine for Geriatric Diseases, School of Public Health, Soochow University, Suzhou, 215123, PR China.
| | - Da-Bing Lu
- Department of Epidemiology and Statistics, School of Public Health, Soochow University, Suzhou, 215123, China.
- Jiangsu Key Laboratory of Preventive and Translational Medicine for Geriatric Diseases, School of Public Health, Soochow University, Suzhou, 215123, PR China.
| | - Huan Ding
- Department of Epidemiology and Statistics, School of Public Health, Soochow University, Suzhou, 215123, China.
- Jiangsu Key Laboratory of Preventive and Translational Medicine for Geriatric Diseases, School of Public Health, Soochow University, Suzhou, 215123, PR China.
| | - Poppy H L Lamberton
- Department of Infectious Disease Epidemiology, Imperial College London, London, W2 1PG, UK.
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Wang J, Wang S, Liu X, Xu B, Chai R, Zhou P, Ju C, Sun J, Brindley PJ, Hu W. Intake of Erythrocytes Required for Reproductive Development of Female Schistosoma japonicum. PLoS One 2015; 10:e0126822. [PMID: 25978643 PMCID: PMC4433235 DOI: 10.1371/journal.pone.0126822] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Accepted: 04/08/2015] [Indexed: 01/09/2023] Open
Abstract
The reproductive development and maturation of female schistosomes are crucial since their released eggs are responsible for the host immunopathology and transmission of schistosomiasis. However, little is known about the nutrients required by female Schistosoma japonicum during its sexual maturation. We evaluated the promoting effect of several nutrients (calf serum, red blood cells (RBCs), ATP and hypoxanthine) on the reproductive development of pre-adult females at 18 days post infection (dpi) from mixed infections and at 50 dpi from unisexual infections of laboratory mice in basic medium RPMI-1640. We found RBCs, rather than other nutrients, promoted the female sexual maturation and egg production with significant morphological changes. In 27% of females (18 dpi) from mixed infections that paired with males in vitro on day 14, vitelline glands could be positively stained by Fast Blue B; and in 35% of females (50 dpi) from unisexual infections on day 21, mature vitelline cells were observed. Infertile eggs were detected among both groups. To analyze which component of mouse RBCs possesses the stimulating effect, RBCs were fractionated and included in media. However, the RBC fractions failed to stimulate development of the female reproductive organs. In addition, bovine hemoglobin hydrolysate, digested by neutral protease, was found to exhibit the promoting activity instead of untreated bovine hemoglobin. The other protein hydrolysate, lactalbumin hydrolysate, exhibited a similar effect with bovine hemoglobin hydrolysate. Using quantitative RT-PCR, we found the expression levels of four reproduction-related genes were significantly stimulated by RBCs. These data indicate that RBCs provide essential nutrients for the sexual maturation of female S. japonicum and that the protein component of RBCs appeared to constitute the key nutrient. These findings would improve laboratory culture of pre-adult schistosomes to adult worms in medium with well-defined components, which is important to investigate the function of genes related to female sexual maturation.
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Affiliation(s)
- Jipeng Wang
- Department of Microbiology and Microbial Engineering, School of Life Sciences, Fudan University, Shanghai, China
| | - Shuqi Wang
- Department of Microbiology and Microbial Engineering, School of Life Sciences, Fudan University, Shanghai, China
| | - Xiufeng Liu
- Department of Microbiology and Microbial Engineering, School of Life Sciences, Fudan University, Shanghai, China
| | - Bin Xu
- Key Laboratory of Parasite and Vector Biology of Ministry of Public Health, Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai, China
| | - Riyi Chai
- Department of Microbiology and Microbial Engineering, School of Life Sciences, Fudan University, Shanghai, China
| | - Pan Zhou
- Department of Microbiology and Microbial Engineering, School of Life Sciences, Fudan University, Shanghai, China
| | - Chuan Ju
- Key Laboratory of Parasite and Vector Biology of Ministry of Public Health, Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai, China
| | - Jun Sun
- Institute for Infectious Diseases and Vaccine development, Tongji University School of Medicine, Shanghai, China
| | - Paul J. Brindley
- Department of Microbiology, Immunology & Tropical Medicine, and Research Center for the Neglected Diseases of Poverty, School of Medicine & Health Sciences, George Washington University, Washington, DC, United States of America
| | - Wei Hu
- Department of Microbiology and Microbial Engineering, School of Life Sciences, Fudan University, Shanghai, China
- Key Laboratory of Parasite and Vector Biology of Ministry of Public Health, Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai, China
- * E-mail:
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Bian CR, Gao YM, Lamberton PHL, Lu DB. Comparison of genetic diversity and population structure between two Schistosoma japonicum isolates—the field and the laboratory. Parasitol Res 2015; 114:2357-62. [DOI: 10.1007/s00436-015-4433-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2015] [Accepted: 03/11/2015] [Indexed: 12/01/2022]
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19
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Yin M, Li H, McManus DP, Blair D, Su J, Yang Z, Xu B, Feng Z, Hu W. Geographical genetic structure of Schistosoma japonicum revealed by analysis of mitochondrial DNA and microsatellite markers. Parasit Vectors 2015; 8:150. [PMID: 25881113 PMCID: PMC4372230 DOI: 10.1186/s13071-015-0757-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2014] [Accepted: 02/20/2015] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Schistosoma japonicum is a significant public health risk in parts of China and elsewhere in Southeast Asia. To gain an insight into the epidemiology of schistosomiasis japonica, a detailed investigation of S. japonicum genetic population structure is needed. METHODS Using three mitochondrial DNA fragments and ten microsatellite loci, we investigated the genetic diversity within and structure among twelve populations of S. japonicum sampled on a geographical scale covering most major endemic areas. RESULTS Schistosoma japonicum lineages from Indonesia, the Philippines and Chinese Taiwan were clearly distinct from each other and from those in mainland China. Within mainland China, there was some evidence for genetic divergence between populations from the mountain and lake regions. However, the analysis inferred no clear sub-population structure in the lake region of mainland China. High genetic diversity was found among S. japonicum populations of mainland China and this was significantly higher than those from island regions. CONCLUSIONS High genetic diversity within and substantial differentiation among populations were demonstrated in S. japonicum.
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Affiliation(s)
- Mingbo Yin
- School of Life Science, Fudan University, Handan Road 220, Shanghai, 200433, China.
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, 207 Rui Jin Er Road, Shanghai, 200025, China.
| | - Hongyan Li
- School of Life Science, Fudan University, Handan Road 220, Shanghai, 200433, China.
| | - Donald P McManus
- QIMR Berghofer Medical Research Institute, 300 Herston Road, Brisbane, Qld 4029, Australia.
| | - David Blair
- School of Marine and Tropical Biology, James Cook University, Townsville, Qld 4811, Australia.
| | - Jing Su
- School of Life Science, Fudan University, Handan Road 220, Shanghai, 200433, China.
| | - Zhong Yang
- School of Life Science, Fudan University, Handan Road 220, Shanghai, 200433, China.
| | - Bin Xu
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, 207 Rui Jin Er Road, Shanghai, 200025, China.
| | - Zheng Feng
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, 207 Rui Jin Er Road, Shanghai, 200025, China.
| | - Wei Hu
- School of Life Science, Fudan University, Handan Road 220, Shanghai, 200433, China.
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, 207 Rui Jin Er Road, Shanghai, 200025, China.
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French MD, Churcher TS, Basáñez MG, Norton AJ, Lwambo NJ, Webster JP. Reductions in genetic diversity of Schistosoma mansoni populations under chemotherapeutic pressure: the effect of sampling approach and parasite population definition. Acta Trop 2013; 128:196-205. [PMID: 22440199 DOI: 10.1016/j.actatropica.2012.03.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2011] [Revised: 03/02/2012] [Accepted: 03/04/2012] [Indexed: 10/28/2022]
Abstract
Detecting potential changes in genetic diversity in schistosome populations following chemotherapy with praziquantel (PZQ) is crucial if we are to fully understand the impact of such chemotherapy with respect to the potential emergence of resistance and/or other evolutionary outcomes of interventions. Doing so by implementing effective, and cost-efficient sampling protocols will help to optimise time and financial resources, particularly relevant to a disease such as schistosomiasis currently reliant on a single available drug. Here we explore the effect on measures of parasite genetic diversity of applying various field sampling approaches, both in terms of the number of (human) hosts sampled and the number of transmission stages (miracidia) sampled per host for a Schistosoma mansoni population in Tanzania pre- and post-treatment with PZQ. In addition, we explore population structuring within and between hosts by comparing the estimates of genetic diversity obtained assuming a 'component population' approach with those using an 'infrapopulation' approach. We found that increasing the number of hosts sampled, rather than the number of miracidia per host, gives more robust estimates of genetic diversity. We also found statistically significant population structuring (using Wright's F-statistics) and significant differences in the measures of genetic diversity depending on the parasite population definition. The relative advantages, disadvantages and, hence, subsequent reliability of these metrics for parasites with complex life-cycles are discussed, both for the specific epidemiological and ecological scenario under study here and for their future application to other areas and schistosome species.
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Korsunenko A, Chrisanfova G, Arifov A, Ryskov A, Semyenova S. Characterization of randomly amplified polymorphic DNA (RAPD) fragments revealing clonal variability in cercariae of avian schistosome <i>Trichobilharzia szidati</i> (Trematoda: Schistosomatidae). ACTA ACUST UNITED AC 2013. [DOI: 10.4236/ojgen.2013.33017] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Zhao GH, Li J, Blair D, Li XY, Elsheikha HM, Lin RQ, Zou FC, Zhu XQ. Biotechnological advances in the diagnosis, species differentiation and phylogenetic analysis of Schistosoma spp. Biotechnol Adv 2012; 30:1381-9. [DOI: 10.1016/j.biotechadv.2012.02.008] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2011] [Revised: 01/08/2012] [Accepted: 02/08/2012] [Indexed: 11/26/2022]
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Rinaldi G, Eckert SE, Tsai IJ, Suttiprapa S, Kines KJ, Tort JF, Mann VH, Turner DJ, Berriman M, Brindley PJ. Germline transgenesis and insertional mutagenesis in Schistosoma mansoni mediated by murine leukemia virus. PLoS Pathog 2012; 8:e1002820. [PMID: 22911241 PMCID: PMC3406096 DOI: 10.1371/journal.ppat.1002820] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2012] [Accepted: 06/11/2012] [Indexed: 12/11/2022] Open
Abstract
Functional studies will facilitate characterization of role and essentiality of newly available genome sequences of the human schistosomes, Schistosoma mansoni, S. japonicum and S. haematobium. To develop transgenesis as a functional approach for these pathogens, we previously demonstrated that pseudotyped murine leukemia virus (MLV) can transduce schistosomes leading to chromosomal integration of reporter transgenes and short hairpin RNA cassettes. Here we investigated vertical transmission of transgenes through the developmental cycle of S. mansoni after introducing transgenes into eggs. Although MLV infection of schistosome eggs from mouse livers was efficient in terms of snail infectivity, >10-fold higher transgene copy numbers were detected in cercariae derived from in vitro laid eggs (IVLE). After infecting snails with miracidia from eggs transduced by MLV, sequencing of genomic DNA from cercariae released from the snails also revealed the presence of transgenes, demonstrating that transgenes had been transmitted through the asexual developmental cycle, and thereby confirming germline transgenesis. High-throughput sequencing of genomic DNA from schistosome populations exposed to MLV mapped widespread and random insertion of transgenes throughout the genome, along each of the autosomes and sex chromosomes, validating the utility of this approach for insertional mutagenesis. In addition, the germline-transmitted transgene encoding neomycin phosphotransferase rescued cultured schistosomules from toxicity of the antibiotic G418, and PCR analysis of eggs resulting from sexual reproduction of the transgenic worms in mice confirmed that retroviral transgenes were transmitted to the next (F1) generation. These findings provide the first description of wide-scale, random insertional mutagenesis of chromosomes and of germline transmission of a transgene in schistosomes. Transgenic lines of schistosomes expressing antibiotic resistance could advance functional genomics for these significant human pathogens. DATABASE ACCESSION: Sequence data from this study have been submitted to the European Nucleotide Archive (http://www.ebi.ac.uk/embl) under accession number ERP000379.
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Affiliation(s)
- Gabriel Rinaldi
- Department of Microbiology, Immunology & Tropical Medicine, School of Medicine & Health Sciences, The George Washington University, Washington, DC, United States of America
- Departamento de Genética, Facultad de Medicina, Universidad de la República, (UDELAR), Montevideo, Uruguay
| | - Sabine E. Eckert
- The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, United Kingdom
- Oxford Nanopore Technologies, Oxford, United Kingdom
| | - Isheng J. Tsai
- The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, United Kingdom
| | - Sutas Suttiprapa
- Department of Microbiology, Immunology & Tropical Medicine, School of Medicine & Health Sciences, The George Washington University, Washington, DC, United States of America
- Department of Pathobiology, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Kristine J. Kines
- Department of Microbiology, Immunology & Tropical Medicine, School of Medicine & Health Sciences, The George Washington University, Washington, DC, United States of America
- Tulane Cancer Center, Tulane University Health Sciences Center, New Orleans, Louisiana, United States of America
| | - José F. Tort
- Departamento de Genética, Facultad de Medicina, Universidad de la República, (UDELAR), Montevideo, Uruguay
| | - Victoria H. Mann
- Department of Microbiology, Immunology & Tropical Medicine, School of Medicine & Health Sciences, The George Washington University, Washington, DC, United States of America
| | - Daniel J. Turner
- The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, United Kingdom
- Oxford Nanopore Technologies, Oxford, United Kingdom
| | - Matthew Berriman
- The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, United Kingdom
| | - Paul J. Brindley
- Department of Microbiology, Immunology & Tropical Medicine, School of Medicine & Health Sciences, The George Washington University, Washington, DC, United States of America
- Research Center for Neglected Diseases of Poverty, The George Washington University, Washington, DC, United States of America
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Hauswald AK, Remais JV, Xiao N, Davis GM, Lu D, Bale MJ, Wilke T. Stirred, not shaken: genetic structure of the intermediate snail host Oncomelania hupensis robertsoni in an historically endemic schistosomiasis area. Parasit Vectors 2011; 4:206. [PMID: 22029536 PMCID: PMC3226449 DOI: 10.1186/1756-3305-4-206] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2011] [Accepted: 10/26/2011] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Oncomelania hupensis robertsoni is the sole intermediate host for Schistosoma japonicum in western China. Given the close co-evolutionary relationships between snail host and parasite, there is interest in understanding the distribution of distinct snail phylogroups as well as regional population structures. Therefore, this study focuses on these aspects in a re-emergent schistosomiasis area known to harbour representatives of two phylogroups - the Deyang-Mianyang area in Sichuan Province, China. Based on a combination of mitochondrial and nuclear DNA, the following questions were addressed: 1) the phylogeography of the two O. h. robertsoni phylogroups, 2) regional and local population structure in space and time, and 3) patterns of local dispersal under different isolation-by-distance scenarios. RESULTS The phylogenetic analyses confirmed the existence of two distinct phylogroups within O. h. robertsoni. In the study area, phylogroups appear to be separated by a mountain range. Local specimens belonging to the respective phylogroups form monophyletic clades, indicating a high degree of lineage endemicity. Molecular clock estimations reveal that local lineages are at least 0.69-1.58 million years (My) old and phylogeographical analyses demonstrate that local, watershed and regional effects contribute to population structure. For example, Analyses of Molecular Variances (AMOVAs) show that medium-scale watersheds are well reflected in population structures and Mantel tests indicate isolation-by-distance effects along waterways. CONCLUSIONS The analyses revealed a deep, complex and hierarchical structure in O. h. robertsoni, likely reflecting a long and diverse evolutionary history. The findings have implications for understanding disease transmission. From a co-evolutionary standpoint, the divergence of the two phylogroups raises species level questions in O. h. robertsoni and also argues for future studies relative to the distinctness of the respective parasites. The endemicity of snail lineages at the regional level supports the concept of endemic schistosomiasis areas and calls for future geospatial analyses for a better understanding of respective boundaries. Finally, local snail dispersal mainly occurs along waterways and can be best described by using cost distance, thus potentially enabling a more precise modelling of snail, and therefore, parasite dispersal.
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Affiliation(s)
- Anne-Kathrin Hauswald
- Department of Animal Ecology & Systematics, Justus Liebig University, Heinrich-Buff-Ring 26-32 IFZ, Giessen, Germany
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Seto EYW, Remais JV, Carlton EJ, Wang S, Liang S, Brindley PJ, Qiu D, Spear RC, Wang LD, Wang TP, Chen HG, Dong XQ, Wang LY, Hao Y, Bergquist R, Zhou XN. Toward sustainable and comprehensive control of schistosomiasis in China: lessons from Sichuan. PLoS Negl Trop Dis 2011; 5:e1372. [PMID: 22039563 PMCID: PMC3201916 DOI: 10.1371/journal.pntd.0001372] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Triggered by a fascinating publication in the New England Journal of Medicine detailing China's new multi-pronged strategy to control and eventually interrupt the transmission of Schistosoma japonicum, this PLoS Neglected Tropical Diseases Debate critically examines the generalizability and financial costs of the studies presented from the marshlands of the lake region. Edmund Seto from the University of California and colleagues emphasize that the epidemiology and control of schistosomiasis varies according to the social-ecological context. They conjecture that the successful intervention packages piloted in the lake region is not fully fit for the hilly and mountainous environments in Sichuan and Yunnan provinces, and hence call for more flexible, setting-specific, and less expensive control strategies. In response, Xiao-Nong Zhou from the National Institute of Parasitic Diseases at the Chinese Center of Disease Control and Prevention and colleagues explain the steps from designing pilot studies to the articulation and implementation of a new national control strategy through a careful process of scaling-up and adaptations. Finally, the two opponents converge. The need for integrated, intersectoral, and setting-specific control measures is stressed, supported by rigorous surveillance and continuous research. Experiences and lessons from China are important for shaping the schistosomiasis elimination agenda.
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Affiliation(s)
- Edmund Y. W. Seto
- School of Public Health, University of California, Berkeley, California, United States of America
- * E-mail: (EYWS); (X-NZ)
| | - Justin V. Remais
- Rollins School of Public Health, Emory University, Atlanta, Georgia, United States of America
| | - Elizabeth J. Carlton
- School of Public Health, University of California, Berkeley, California, United States of America
| | - Shuo Wang
- School of Public Health, University of California, Berkeley, California, United States of America
| | - Song Liang
- College of Public Health, The Ohio State University, Columbus, Ohio, United States of America
| | - Paul J. Brindley
- Department of Microbiology, Immunology & Tropical Medicine, George Washington University Medical Center, Washington, D.C., United States of America
| | - Dongchuan Qiu
- Institute of Parasitic Diseases, Sichuan Center for Disease Control and Prevention, Chengdu, People's Republic of China
| | - Robert C. Spear
- School of Public Health, University of California, Berkeley, California, United States of America
| | - Long-De Wang
- School of Public Health, Peking University, Beijing, People's Republic of China
| | - Tian-Ping Wang
- Anhui Institute of Parasitic Diseases, Wuhu, People's Republic of China
| | - Hong-Gen Chen
- Jiangxi Institute of Parasitic Diseases, Nanchang, People's Republic of China
| | - Xing-Qi Dong
- Yunnan Institute of Endemic Diseases, Dali, People's Republic of China
| | - Li-Ying Wang
- Ministry of Health, Beijing, People's Republic of China
| | - Yang Hao
- Ministry of Health, Beijing, People's Republic of China
| | | | - Xiao-Nong Zhou
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai, People's Republic of China
- * E-mail: (EYWS); (X-NZ)
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Cupit PM, Steinauer ML, Tonnessen BW, Agola LE, Kinuthia JM, Mwangi IN, Mutuku MW, Mkoji GM, Loker ES, Cunningham C. Polymorphism associated with the Schistosoma mansoni tetraspanin-2 gene. Int J Parasitol 2011; 41:1249-52. [PMID: 21889508 PMCID: PMC3188324 DOI: 10.1016/j.ijpara.2011.07.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2011] [Revised: 07/24/2011] [Accepted: 07/27/2011] [Indexed: 10/17/2022]
Abstract
A vaccine against schistosomiasis would contribute significantly to reducing the 3-70 million disability-adjusted life years lost annually to the disease. Towards this end, inoculation with the large extracellular loop (EC-2) of Schistosoma mansoni tetraspanin-2 protein (Sm-TSP-2) has proved effective in reducing worm and egg burdens in S. mansoni-infected mice. The EC-2 loop of Schistosoma japonicum TSP-2, however, has been found to be highly polymorphic, perhaps diminishing the likelihood that this antigen can be used for vaccination against this species. Here, we examine polymorphism of the EC-2 of Sm-TSP-2 in genetically unique worms derived from six individuals from Kisumu, Kenya.
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Affiliation(s)
- Pauline M. Cupit
- Center for Evolutionary and Theoretical Immunology, Department of Biology, University of New Mexico, Albuquerque, New Mexico, USA
| | | | - Bradley W. Tonnessen
- Center for Evolutionary and Theoretical Immunology, Department of Biology, University of New Mexico, Albuquerque, New Mexico, USA
| | - L. Eric Agola
- Centre for Biotechnology Research and Development, Kenya Medical Research Institute, Nairobi, Kenya
| | - Joseph M. Kinuthia
- Centre for Biotechnology Research and Development, Kenya Medical Research Institute, Nairobi, Kenya
| | - Ibrahim N. Mwangi
- Centre for Biotechnology Research and Development, Kenya Medical Research Institute, Nairobi, Kenya
| | - Martin W. Mutuku
- Centre for Biotechnology Research and Development, Kenya Medical Research Institute, Nairobi, Kenya
| | - Gerald M. Mkoji
- Centre for Biotechnology Research and Development, Kenya Medical Research Institute, Nairobi, Kenya
| | - Eric S. Loker
- Center for Evolutionary and Theoretical Immunology, Department of Biology, University of New Mexico, Albuquerque, New Mexico, USA
| | - Charles Cunningham
- Center for Evolutionary and Theoretical Immunology, Department of Biology, University of New Mexico, Albuquerque, New Mexico, USA
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Genetic differentiation of cercariae infrapopulations of the avian schistosome Trichobilharzia szidati based on RAPD markers and mitochondrial cox1 gene. Parasitol Res 2011; 110:833-41. [PMID: 21796386 DOI: 10.1007/s00436-011-2562-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2011] [Accepted: 07/13/2011] [Indexed: 10/17/2022]
Abstract
Avian schistosome Trichobilharzia szidati is a member of the largest genus within the family Schistosomatidae (Trematoda). Population genetic structure of Trichobilharzia spp. schistosomes, causative agents of cercarial dermatitis in humans, has not been studied yet. The knowledge of the genetic structure of trichobilharzian populations is essential for understanding the host-parasite coevolutionary dynamics and epidemiology strategies. Here we examined genetic diversity in three geographically isolated local populations of T. szidati cercariae inhabiting Russia based on nuclear (randomly amplified polymorphic DNA, RAPD) and mt (cox1) markers. We analyzed T. szidati cercariae shed from seven naturally infected snails of Lymnaea stagnalis. Using three random primers, we demonstrated genetic variation among populations, thus posing genetic structure across geographic sites. Moreover, T. szidati cercariae have been genetically structured among hosts (infrapopulations). Molecular variance analysis was performed to test the significance of genetic differentiation within and between local populations. Of total parasitic diversity, 18.8% was partitioned between populations, whereas the higher contribution (48.9%) corresponds to the differences among individual cercariae within infrapopulations. In contrast to RAPD markers, a 1,125-bp fragment of cox1 mt gene failed to provide any significant within-species structure. The lack of geographic structuring was detected using unique haplotypes which were determined in the current work for Moscow and Western Siberian local populations as well as obtained previously for European isolates (Czech Republic and Germany). All T. szidati/Trichobilharzia ocellata haplotypes were found to be mixed across their geographical origin.
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Song HQ, Mo XH, Zhao GH, Li J, Zou FC, Liu W, Wu XY, Lin RQ, Weng YB, Zhu XQ. Electrophoretic detection of genetic variability among Schistosoma japonicum isolates by sequence-related amplified polymorphism. Electrophoresis 2011; 32:1364-70. [PMID: 21538983 DOI: 10.1002/elps.201000600] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2010] [Revised: 12/27/2010] [Accepted: 01/05/2011] [Indexed: 11/12/2022]
Abstract
In the present study, sequence-related amplification polymorphism (SRAP) was utilized to study the genetic variability among Schistosoma japonicum isolates from different provinces in China, using Schistosoma mansoni from Puerto Rico for comparison. Five out of ten tested SRAP primer combinations displayed significant polymorphisms among S. japonicum isolates from China, namely ME2/EM1, ME4/EM1, ME4/EM6, ME5/EM4 and ME5/EM5. Analysis of the 61 S. japonicum samples from China with five SRAP primer combinations identified a total of 83 reproducible polymorphic fragments. The number of fragments using each primer combination ranged from 14 to 19, with an average of 16 polymorphic bands per primer pair, and the size of fragment ranged approximately from 100 to 1000 bp. Representative-specific SRAP fragments were excised from the gels, and confirmed by PCR amplification of genomic DNA using primers designed and based on the sequences of these SRAP fragments. Based on SRAP profiles, unweighted pair-group method with arithmetic averages (UPGMA) dendrogram was constructed. UPGMA clustering algorithm categorized S. japonicum isolates from China into nine clades and two lineages (representing the mountainous and lake/marshland regions). These results indicate the usefulness of the SRAP technique for revealing genetic variability among S. japonicum isolates from China, and the SRAP technique should be applicable to other living organisms.
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Affiliation(s)
- Hui-Qun Song
- State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, CAAS, Lanzhou, Gansu Province, P. R. China
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Xiao N, Remais J, Brindley PJ, Qiu D, Spear R, Lei Y, Blair D. Polymorphic microsatellites in the human bloodfluke, Schistosoma japonicum, identified using a genomic resource. Parasit Vectors 2011; 4:13. [PMID: 21299863 PMCID: PMC3042964 DOI: 10.1186/1756-3305-4-13] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2010] [Accepted: 02/07/2011] [Indexed: 11/17/2022] Open
Abstract
Re-emergence of schistosomiasis in regions of China where control programs have ceased requires development of molecular-genetic tools to track gene flow and assess genetic diversity of Schistosoma populations. We identified many microsatellite loci in the draft genome of Schistosoma japonicum using defined search criteria and selected a subset for further analysis. From an initial panel of 50 loci, 20 new microsatellites were selected for eventual optimization and application to a panel of worms from endemic areas. All but one of the selected microsatellites contain simple tri-nucleotide repeats. Moderate to high levels of polymorphism were detected. Numbers of alleles ranged from 6 to 14 and observed heterozygosity was always >0.6. The loci reported here will facilitate high resolution population-genetic studies on schistosomes in re-emergent foci.
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Affiliation(s)
- Ning Xiao
- Institute of Parasitic Diseases, Sichuan Center for Disease Control and Prevention, Chengdu, Sichuan 610041, PR China.
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Bahia D, Rodrigues NB, Araújo FMG, Romanha AJ, Ruiz JC, Johnston DA, Oliveira G. CA88, a nuclear repetitive DNA sequence identified in Schistosoma mansoni, aids in the genotyping of nine Schistosoma species of medical and veterinary importance. Mem Inst Oswaldo Cruz 2011; 105:391-7. [PMID: 20721481 DOI: 10.1590/s0074-02762010000400008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2008] [Accepted: 02/10/2010] [Indexed: 11/22/2022] Open
Abstract
CA88 is the first long nuclear repetitive DNA sequence identified in the blood fluke, Schistosoma mansoni. The assembled S. mansoni sequence, which contains the CA88 repeat, has 8,887 nucleotides and at least three repeat units of approximately 360 bp. In addition, CA88 also possesses an internal CA microsatellite, identified as SmBr18. Both PCR and BLAST analysis have been used to analyse and confirm the CA88 sequence in other S. mansoni sequences in the public database. PCR-acquired nuclear repetitive DNA sequence profiles from nine Schistosoma species were used to classify this organism into four genotypes. Included among the nine species analysed were five sequences of both African and Asian lineages that are known to infect humans. Within these genotypes, three of them refer to recognised species groups. A panel of four microsatellite loci, including SmBr18 and three previously published loci, has been used to characterise the nine Schistosoma species. Each species has been identified and classified based on its CA88 DNA fingerprint profile. Furthermore, microsatellite sequences and intra-specific variation have also been observed within the nine Schistosoma species sequences. Taken together, these results support the use of these markers in studying the population dynamics of Schistosoma isolates from endemic areas and also provide new methods for investigating the relationships between different populations of parasites. In addition, these data also indicate that Schistosoma magrebowiei is not a sister taxon to Schistosoma mattheei, prompting a new designation to a basal clade.
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Affiliation(s)
- Diana Bahia
- Departamento de Microbiologia, Imunologia e Parasitologia, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP, Brasil.
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Lu DB, Rudge JW, Wang TP, Donnelly CA, Fang GR, Webster JP. Transmission of Schistosoma japonicum in marshland and hilly regions of China: parasite population genetic and sibship structure. PLoS Negl Trop Dis 2010; 4:e781. [PMID: 20689829 PMCID: PMC2914789 DOI: 10.1371/journal.pntd.0000781] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2009] [Accepted: 07/01/2010] [Indexed: 11/25/2022] Open
Abstract
The transmission dynamics of Schistosoma japonicum remain poorly understood, as over forty species of mammals are suspected of serving as reservoir hosts. However, knowledge of the population genetic structure and of the full-sibship structuring of parasites at two larval stages will be useful in defining and tracking the transmission pattern between intermediate and definitive hosts. S. japonicum larvae were therefore collected in three marshland and three hilly villages in Anhui Province of China across three time points: April and September-October 2006, and April 2007, and then genotyped with six microsatellite markers. Results from the population genetic and sibling relationship analyses of the parasites across two larval stages demonstrated that, within the marshland, parasites from cattle showed higher genetic diversity than from other species; whereas within the hilly region, parasites from dogs and humans displayed higher genetic diversity than those from rodents. Both the extent of gene flow and the estimated proportion of full-sib relationships of parasites between two larval stages indicated that the cercariae identified within intermediate hosts in the marshlands mostly came from cattle, whereas in the hilly areas, they were varied between villages, coming primarily from rodents, dogs or humans. Such results suggest a different transmission process within the hilly region from within the marshlands. Moreover, this is the first time that the sibling relationship analysis was applied to the transmission dynamics for S. japonicum. Schistosoma japonicum involves two obligatory host stages, with asexual reproduction within a molluscan host and sexual reproduction within a mammalian host. Having over 40 species of mammals suspected of being potential reservoirs complicates the transmission patterns. Understanding the complex transmission patterns is further hampered by the ethical and logistical difficulty in sampling adult worms from mammalian hosts. However, the two free-swimming larval stages, cercariae (released from a mollusc and then infective to a mammal) and miracidia (hatched from eggs passed in a mammal's faeces, and then infective to a mollusc), are available, and elucidating the genetic composition of parasites at theses two stages could provide information of infection processes. Here we sampled cercariae during April 2006, miracidia during September-October 2006, and cercariae during April 2007 in three marshland and three hilly villages in Anhui Province of China, and, using microsatellite markers, analyzed the population genetic structure and, for the first time, the familial relationships of parasites at different stages. We found contrasting population structures of parasites, and host species-associated diversities and transmission patterns of parasites between and within two regions. Moreover, we demonstrate that the successful application of sibship analyses to infection process provides an alternative approach to the dissection of transmission dynamics.
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Affiliation(s)
- Da-Bing Lu
- Department of Infectious Disease Epidemiology, Faculty of Medicine, Imperial College, London, UK.
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Schistosomiasis in the People's Republic of China: the era of the Three Gorges Dam. Clin Microbiol Rev 2010; 23:442-66. [PMID: 20375361 DOI: 10.1128/cmr.00044-09] [Citation(s) in RCA: 166] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The potential impact of the Three Gorges Dam (TGD) on schistosomiasis transmission in China has invoked considerable global concern. The TGD will result in changes in the water level and silt deposition downstream, favoring the reproduction of Oncomelania snails. Combined with blockages of the Yangtze River's tributaries, these changes will increase the schistosomiasis transmission season within the marshlands along the middle and lower reaches of the Yangtze River. The changing schistosome transmission dynamics necessitate a comprehensive strategy to control schistosomiasis. This review discusses aspects of the epidemiology and transmission of Schistosoma japonicum in China and considers the pathology, clinical outcomes, diagnosis, treatment, immunobiology, and genetics of schistosomiasis japonica together with an overview of current progress in vaccine development, all of which will have an impact on future control efforts. The use of synchronous praziquantel (PZQ) chemotherapy for humans and domestic animals is only temporarily effective, as schistosome reinfection occurs rapidly. Drug delivery requires a substantial infrastructure to regularly cover all parts of an area of endemicity. This makes chemotherapy expensive and, as compliance is often low, a less than satisfactory control option. There is increasing disquiet about the possibility that PZQ-resistant schistosomes will develop. Consequently, as mathematical modeling predicts, vaccine strategies represent an essential component in the future control of schistosomiasis in China. With the inclusion of focal mollusciciding, improvements in sanitation, and health education into the control scenario, China's target of reducing the level of schistosome infection to less than 1% by 2015 may be achievable.
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Steinauer ML, Blouin MS, Criscione CD. Applying evolutionary genetics to schistosome epidemiology. INFECTION, GENETICS AND EVOLUTION : JOURNAL OF MOLECULAR EPIDEMIOLOGY AND EVOLUTIONARY GENETICS IN INFECTIOUS DISEASES 2010; 10:433-43. [PMID: 20176142 PMCID: PMC2861999 DOI: 10.1016/j.meegid.2010.02.007] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2009] [Revised: 02/09/2010] [Accepted: 02/15/2010] [Indexed: 10/19/2022]
Abstract
We review how molecular markers and evolutionary analysis have been applied to the study of schistosome parasites, important pathogens that infect over 200 million people worldwide. Topics reviewed include phylogenetics and biogeography, hybridization, infection within snails, mating systems, and genetic structure. Some interesting generalizations include that schistosome species hybridize frequently and have switched definitive hosts repeatedly in evolutionary time. We show that molecular markers can be used to infer epidemiologically relevant processes such as spatial variation in transmission, or to reveal complex patterns of mate choice. Analysis of genetic structure data shows that transmission foci can be structured by watershed boundaries, habitat types, and host species. We also discuss sampling and analytical problems that arise when using larvae to estimate genetic parameters of adult schistosome populations. Finally, we review pitfalls in methodologies such as genotyping very small individuals, statistical methods for identifying clonemates or for identifying sibling groups, and estimating allele frequencies from pooled egg samples.
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Affiliation(s)
- Michelle L Steinauer
- Department of Biomedical Sciences, College of Veterinary Medicine, Oregon State University, 105 Magruder Hall, Corvallis, OR 97331, United States.
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Lu DB, Wang TP, Rudge JW, Donnelly CA, Fang GR, Webster JP. Evolution in a multi-host parasite: Chronobiological circadian rhythm and population genetics of Schistosoma japonicum cercariae indicates contrasting definitive host reservoirs by habitat. Int J Parasitol 2009; 39:1581-8. [DOI: 10.1016/j.ijpara.2009.06.003] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2009] [Revised: 06/03/2009] [Accepted: 06/10/2009] [Indexed: 11/16/2022]
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Steinauer ML. The sex lives of parasites: investigating the mating system and mechanisms of sexual selection of the human pathogen Schistosoma mansoni. Int J Parasitol 2009; 39:1157-63. [PMID: 19298820 PMCID: PMC2911351 DOI: 10.1016/j.ijpara.2009.02.019] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2009] [Revised: 02/10/2009] [Accepted: 02/12/2009] [Indexed: 01/28/2023]
Abstract
The mating systems of internal parasites are inherently difficult to investigate although they have important implications for the evolutionary biology of the species, disease epidemiology, and are important considerations for control measures. Using parentage analyses, three topics concerning the mating biology of Schistosoma mansoni were investigated: the number of mates per adult male and female, variance in reproductive success among individuals, and the potential role for sexual selection on male body size and also mate choice for genetically dissimilar individuals. Results indicated that schistosomes were mostly monogamous, and evidence of only one mate change occurred over a period of 5-6 weeks. One male was polygynous and contained two females in its gynecophoral canal although offspring were only detected for one of the females. Even though they were primarily monogamous and the sex ratio near even, reproductive success was highly variable, indicating a potential role for sexual selection. Male body size was positively related to reproductive success, consistent with sexual selection via male-male competition and female choice for large males. However, relatedness of pairs was not associated with their reproductive success. Finally, genetically identical individuals differed significantly in their reproductive output and identical males in their body size, indicating important partner and environmental effects on these traits.
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Rudge JW, Lu DB, Fang GR, Wang TP, Basáñez MG, Webster JP. Parasite genetic differentiation by habitat type and host species: molecular epidemiology of Schistosoma japonicum in hilly and marshland areas of Anhui Province, China. Mol Ecol 2009; 18:2134-47. [PMID: 19389178 DOI: 10.1111/j.1365-294x.2009.04181.x] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Schistosoma japonicum, a parasite of significant public health importance in parts of China and Southeast Asia, is a true generalist pathogen with over 40 species of mammals suspected as definitive host reservoirs. In order to characterize levels of parasite gene flow across host species and identify the most important zoonotic reservoirs, S. japonicum larvae (miracidia) were sampled from a range of definitive host species in two contrasting habitat types within Anhui Province, China: a low-lying marshland region, and a hilly region, where animal reservoir populations may be predicted to differ substantially. Miracidia samples were genotyped using seven multiplexed microsatellite markers. Hierarchical F-statistics and clustering analyses revealed substantial geographical structuring of S. japonicum populations within Anhui, with strong parasite genetic differentiation between habitat types. Within most villages, there was very little or no parasite genetic differentiation among host species, suggesting frequent S. japonicum gene flow, and thus also transmission, across species. Moreover, the data provide novel molecular evidence that rodents and dogs are potentially very important infection reservoirs in hilly regions, in contrast to bovines in the marshland regions. The parasite genetic differentiation between habitat types might therefore be associated with contrasting host reservoirs. The high levels of parasite gene flow observed across host species in sympatric areas have important implications for S. japonicum control, particularly in hilly regions where control of infection among wild rodent populations could be challenging.
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Affiliation(s)
- James W Rudge
- Department of Infectious Disease Epidemiology, Faculty of Medicine, Imperial College London, London, UK.
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