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Sukee T, Beveridge I, Koehler AV, Hall R, Gasser RB, Jabbar A. Phylogenetic relationships of the nematode subfamily Phascolostrongylinae from macropodid and vombatid marsupials inferred using mitochondrial protein sequence data. Parasit Vectors 2021; 14:523. [PMID: 34627345 PMCID: PMC8501563 DOI: 10.1186/s13071-021-05028-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Accepted: 09/18/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The subfamily Phascolostrongylinae (Superfamily Strongyloidea) comprises nematodes that are parasitic in the gastrointestinal tracts of macropodid (Family Macropodidae) and vombatid (Family Vombatidae) marsupials. Currently, nine genera and 20 species have been attributed to the subfamily Phascolostrongylinae. Previous studies using sequence data sets for the internal transcribed spacers (ITS) of nuclear ribosomal DNA showed conflicting topologies between the Phascolostrongylinae and related subfamilies. Therefore, the aim of this study was to validate the phylogenetic relationships within the Phascolostrongylinae and its relationship with the families Chabertiidae and Strongylidae using mitochondrial amino acid sequences. METHODS The sequences of all 12 mitochondrial protein-coding genes were obtained by next-generation sequencing of individual adult nematodes (n = 8) representing members of the Phascolostrongylinae. These sequences were conceptually translated and the phylogenetic relationships within the Phascolostrongylinae and its relationship with the families Chabertiidae and Strongylidae were inferred from aligned, concatenated amino acid sequence data sets. RESULTS Within the Phascolostrongylinae, the wombat-specific genera grouped separately from the genera occurring in macropods. Two of the phascolostrongyline tribes were monophyletic, including Phascolostrongylinea and Hypodontinea, whereas the tribe Macropostrongyloidinea was paraphyletic. The tribe Phascolostrongylinea occurring in wombats was closely related to Oesophagostomum spp., also from the family Chabertiidae, which formed a sister relationship with the Phascolostrongylinae. CONCLUSION The current phylogenetic relationship within the subfamily Phascolostrongylinae supports findings from a previous study based on ITS sequence data. This study contributes also to the understanding of the phylogenetic position of the subfamily Phascolostrongylinae within the Chabertiidae. Future studies investigating the relationships between the Phascolostrongylinae and Cloacininae from macropodid marsupials may advance our knowledge of the phylogeny of strongyloid nematodes in marsupials.
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Affiliation(s)
- Tanapan Sukee
- Department of Veterinary Biosciences, Melbourne Veterinary School, The University of Melbourne, Victoria, Australia.
| | - Ian Beveridge
- Department of Veterinary Biosciences, Melbourne Veterinary School, The University of Melbourne, Victoria, Australia.,South Australian Museum, Adelaide, South Australia, Australia
| | - Anson V Koehler
- Department of Veterinary Biosciences, Melbourne Veterinary School, The University of Melbourne, Victoria, Australia
| | - Ross Hall
- Department of Veterinary Biosciences, Melbourne Veterinary School, The University of Melbourne, Victoria, Australia
| | - Robin B Gasser
- Department of Veterinary Biosciences, Melbourne Veterinary School, The University of Melbourne, Victoria, Australia
| | - Abdul Jabbar
- Department of Veterinary Biosciences, Melbourne Veterinary School, The University of Melbourne, Victoria, Australia
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Morphometrical and Molecular Characterization of Oesophagostomum columbianum (Chabertiidae: Oesophagostominae) and Haemonchus contortus (Trichostrongylidae: Haemonchinae) Isolated from Goat ( Capra hircus) in Sylhet, Bangladesh. J Parasitol Res 2021; 2021:8863283. [PMID: 33708439 PMCID: PMC7932798 DOI: 10.1155/2021/8863283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 02/03/2021] [Accepted: 02/12/2021] [Indexed: 11/17/2022] Open
Abstract
This study was aimed at describing two (2) intestinal nematodes from naturally infected native breed of goats (Capra hircus) in Bangladesh, identified as Oesophagostomum columbianum (Curtice, 1890) Stossich 1899 and Haemonchus contortus (Rudolphi, 1803) Cobb, 1898. The identification was made based on morphometric features and was confirmed by amplifying internal transcribed spacer (ITS) and cytochrome c oxidase (cox1) gene. Well-developed lateral alae, distinct cervical papillae anteriorly to esophageal expansion, and male spicule length (0.73-0.79 mm, n = 2) were characteristically observed in O. columbianum. At the same time, male spicule length (0.40-0.46 mm, n = 2) and position of female vulvar flap (4.30-4.54 mm from posterior end, n = 3) were observed in H. contortus. DNA sequence homology of the ITS and cox1 gene of both specimens revealed the same results, showing similarity to the GenBank sequences of O. columbianum (GenBank No. KC715827; JX188470) and H. contortus (GenBank No. KJ724377; HQ389229). Phylogenetic analysis computed by maximum livelihood (ML) from the ITS nucleotide sequences revealed that the O. columbianum and H. contortus isolates identified in this study were clustered in the same clade with isolates from China and Iran, respectively. This study, for the first time, illustrates the characteristics of O. columbianum and H. contortus in Bangladesh, combining both morphological and molecular data. The universal primer-based polymerase chain reaction (PCR) protocol could be an economical and efficient option for researchers from poor resource settings for precise identification of nematodes. The information generated in this study may contribute to formulating effective control strategies against these nematodes.
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Chabaudstrongylus ninhae (Trichostrongylidae: Cooperiinae) and Oesophagostomum muntiacum (Chabertiidae: Oesophagostominae) in feral alien Reeves's muntjacs on Izu-Oshima Island, Tokyo, Japan. J Helminthol 2019; 94:e48. [PMID: 30973116 DOI: 10.1017/s0022149x19000245] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The naturalization of alien Reeves's muntjacs (Muntiacus reevesi) on Izu-Oshima Island, Tokyo, Japan, has proceeded intensively over the last five decades. To clarify whether the gastrointestinal helminths of these animals were brought from their original endemic area or were newly acquired in Japan, 32 Reeves's muntjacs trapped on the island were parasitologically examined. In addition to Gongylonema pulchrum in the oesophagus (34.4% prevalence), Chabaudstrongylus ninhae (Dróżdż, 1967) (Trichostrongylidae: Cooperiinae) and Oesophagostomum muntiacum Jian, 1989 (Chabertiidae: Oesophagostominae) were prevalent in the small (28.1%) and large (46.9%) intestines, respectively. For the first time, these trichostrongylid or chabertiid worms were genetically characterized based on partial nucleotide sequences of the nuclear ribosomal RNA gene (rDNA) and mitochondrial DNA cytochrome c oxidase subunit 1 gene (cox-1), and the phylogenetic relationships with other members of their family were explored. Since these two intestinal nematode species are inherent in muntjacs, this study demonstrates a new distribution of exotic helminth species in Japan in accordance with the naturalization of alien mammalian hosts. The molecular genetic data collected here could assist the taxonomic assessment of morphological variants in different Muntiacus spp. and/or of different geographical origins. Furthermore, our data may help to define the phylogenetic relationships among such isolates.
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Ashworthius sidemi Schulz, 1933 and Haemonchus contortus (Rudolphi, 1803) in cervids in France: integrative approach for species identification. INFECTION GENETICS AND EVOLUTION 2016; 46:94-101. [DOI: 10.1016/j.meegid.2016.10.027] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Revised: 10/14/2016] [Accepted: 10/29/2016] [Indexed: 11/19/2022]
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Identification of Chabertiidae (Nematoda, Strongylida) by PCR-RFLP based method: a new diagnostic tool for cross transmission investigation between domestic and wild ruminants in France. INFECTION GENETICS AND EVOLUTION 2014; 28:15-20. [PMID: 25194240 DOI: 10.1016/j.meegid.2014.08.027] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2014] [Revised: 06/16/2014] [Accepted: 08/27/2014] [Indexed: 11/23/2022]
Abstract
We describe a PCR-RFLP-based method that allows reliable identification of four species of nematode parasites presenting similar infective third-stage larvae (L3) with a flagelliform tail and more than 16 intestinal cells, commonly observed in gastrointestinal tract of ruminants in France. Molecular analysis of the second internal transcribed spacer (ITS2) of ribosomal DNA, considered as a specific marker for Strongylida, revealed four robust monophyletic clades corresponding to species Chabertia ovina, Oesophagostomum sikae, Oesophagostomum radiatum and Oesophagostomum venulosum. One restriction enzyme (DdeI) was used to digest this domain, and we observed four different and clear digestion patterns according to these species (adults or larvae). Hence, this new method is a good tool easy to use for veterinary laboratories to characterize the different species, and allows considering possible cross transmission between domestic and wild ruminants, especially cervids often incriminated as potential reservoir of parasites for cattle. Moreover, thanks to this new tool, necroscopic analyses could be substituted by coprological methods, a non-invasive approach.
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Ghai RR, Chapman CA, Omeja PA, Davies TJ, Goldberg TL. Nodule worm infection in humans and wild primates in Uganda: cryptic species in a newly identified region of human transmission. PLoS Negl Trop Dis 2014; 8:e2641. [PMID: 24421915 PMCID: PMC3888470 DOI: 10.1371/journal.pntd.0002641] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2013] [Accepted: 11/28/2013] [Indexed: 12/02/2022] Open
Abstract
INTRODUCTION Soil-transmitted helminths (STHs) are a major health concern in tropical and sub-tropical countries. Oesophagostomum infection is considered endemic to West Africa but has also been identified in Uganda, East Africa, among primates (including humans). However, the taxonomy and ecology of Oesophagostomum in Uganda have not been studied, except for in chimpanzees (Pan troglodytes), which are infected by both O. bifurcum and O. stephanostomum. METHODS AND FINDINGS We studied Oesophagostomum in Uganda in a community of non-human primates that live in close proximity to humans. Prevalence estimates based on microscopy were lower than those based on polymerase chain reaction (PCR), indicating greater sensitivity of PCR. Prevalence varied among host species, with humans and red colobus (Procolobus rufomitratus) infected at lowest prevalence (25% and 41% by PCR, respectively), and chimpanzees, olive baboons (Papio anubis), and l'hoest monkeys (Cercopithecus lhoesti) infected at highest prevalence (100% by PCR in all three species). Phylogenetic regression showed that primates travelling further and in smaller groups are at greatest risk of infection. Molecular phylogenetic analyses revealed three cryptic clades of Oesophagostomum that were not distinguishable based on morphological characteristics of their eggs. Of these, the clade with the greatest host range had not previously been described genetically. This novel clade infects humans, as well as five other species of primates. CONCLUSIONS Multiple cryptic forms of Oesophagostomum circulate in the people and primates of western Uganda, and parasite clades differ in host range and cross-species transmission potential. Our results expand knowledge about human Oesophagostomum infection beyond the West African countries of Togo and Ghana, where the parasite is a known public health concern. Oesophagostomum infection in humans may be common throughout Sub-Saharan Africa, and the transmission of this neglected STH among primates, including zoonotic transmission, may vary among host communities depending on their location and ecology.
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Affiliation(s)
- Ria R. Ghai
- Department of Biology, McGill University, Montreal, Quebec, Canada
| | - Colin A. Chapman
- Department of Anthropology and McGill School of Environment, Montreal, Quebec, Canada, and Wildlife Conservation Society, Bronx, New York, New York, United States of America
- Makerere University Biological Field Station, Fort Portal, Uganda
| | - Patrick A. Omeja
- Makerere University Biological Field Station, Fort Portal, Uganda
| | | | - Tony L. Goldberg
- Makerere University Biological Field Station, Fort Portal, Uganda
- Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
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Zhao L, Liu GH, Zhao GH, Cai JZ, Zhu XQ, Qian AD. Genetic differences between Chabertia ovina and C. erschowi revealed by sequence analysis of four mitochondrial genes. ACTA ACUST UNITED AC 2013; 26:167-70. [PMID: 24328823 DOI: 10.3109/19401736.2013.843089] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
This study examined sequence differences in mitochondrial cytochrome c oxidase subunit 1 (cox1), large subunit ribosomal RNA (rrnL) and NADH dehydrogenase subunits 1 and 4 (nad1 and nad4) between Chabertia ovina and C. erschowi from yaks in Qinghai and goats in Shaanxi provinces, China. A part of the cox1 (pcox1), rrnL (prrnL), nad1 and nad4 genes (pnad1 and pnad4) were amplified separately from individual nematodes by PCR and sequenced. The length of the sequences of pcox1, prrnL, pnad1 and pnad4 was 441 bp, 450 bp, 526 bp and 914 bp for C. ovina, and 441 bp, 451 bp, 517 bp and 810 bp for C. erschowi, respectively. The intra-specific sequence variations within C. ovina were 0.2-2.9% for pcox1, 0-0.9% for prrnL, 0.6-2.3% for pnad1, and 0.4-2.0% for pnad4, and were 0.5-1.6% for pcox1, 0-1.1% for prrnL, 0.2-1.7% for pnad1, and 0.4-1.1% for pnad4 within C. erschowi. Whereas, the inter-specific sequence differences between the two species were obviously higher, being 11.6-12.9% for pcox1, 9.8-11.1% for prrnL, 14.4-15.9% for pnad1, and 16.4-17.7% for pnad4. Phylogenetic analyses using Bayesian inference (BI), based on combined sequences of four genes, indicated that the C. ovina and C. erschowi represent distinct species. These results demonstrate that these mt gene sequences provide novel genetic markers for the identificaiton and differentiation C. ovina and C. erschowi, and have implications for studying the population genetics and molecular epidemiology of Chabertia spp.
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Affiliation(s)
- Lei Zhao
- College of Animal Science and Technology, Jilin Agricultural University , Changchun, Jilin Province , P.R. China
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The complete mitochondrial genomes of Oesophagostomum asperum and Oesophagostomum columbianum in small ruminants. INFECTION GENETICS AND EVOLUTION 2013; 19:205-11. [DOI: 10.1016/j.meegid.2013.07.018] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2013] [Revised: 06/11/2013] [Accepted: 07/16/2013] [Indexed: 11/21/2022]
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First description of gastrointestinal nematodes of Barbary sheep (Ammotragus lervia): the case of Camelostrongylus mentulatus as a paradigm of phylogenic and specific relationship between the parasite and its ancient host. Vet Res Commun 2013; 37:209-15. [PMID: 23616093 DOI: 10.1007/s11259-013-9563-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/03/2013] [Indexed: 10/26/2022]
Abstract
The gastrointestinal helminth fauna of 24 Barbary sheep or Aoudad (Ammotragus lervia sahariensis) maintained in the Parque de Rescate de la Fauna Sahariana (PRFS, CSIC, Almeria, Spain) was analyzed. Most animals (87.5 %) were parasitized, and multiple infections were highly present. The following species were identified: Camelostrongylus mentulatus, Teladorsagia circumcincta, Marshallagia marshalli, Ostertagia ostertagi, O. leptospicularis, O. lyrata, Haemonchus contortus, Teladorsagia trifurcata, Trichostrongylus vitrinus, T. colubriformis, T. probolorus, T. capricola, Nematodirus spathiger, N. abnormalis, N. filicollis, N. helvetianus, Trichuris spp. and Skrjabinema ovis. Teladorsagia circumcincta was the most prevalent nematode in abomasum (52.6 %) followed by C. mentulatus (50 %). However, this latter nematode had the greater mean intensity and abundance. In the small intestine, T. colubriformis and T. vitrinus had the highest prevalence (36.4 %); the last one showed also the greater mean intensity and abundance. It should be emphasized the presence of Skrjabinema ovis (prevalence 39.1 %) in the large intestine, showing the greater mean abundance and intensity, although with a low values. Camelostrongylus mentulatus could be the most primitive nematode of the family trichostrongylidae recovered in this study; attending to its high prevalence, mean abundance and mean intensity, the possible specificity between this parasite and the Aoudad is discussed.
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Hasegawa H, Sato H, Suzuki K, Kaneshiro Y. A New Oxyurid Species (Nematoda) Collected from a Japanese Serow,Capricornis crispus(Mammalia: Bovidae), in Japan. J Parasitol 2012; 98:1161-5. [DOI: 10.1645/ge-3133.1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Characterization of Oesophagostomum asperum and O. columbianum by internal transcribed spacers of nuclear ribosomal DNA. J Helminthol 2012. [DOI: 10.1017/s0022149x12000764] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
AbstractIn the present study, the internal transcribed spacers (ITS) of ribosomal DNA (rDNA) of Oesophagostomum asperum and O. columbianum were amplified and sequenced. The ITS-1, 5.8S and ITS-2 rDNA sequences of O. asperum were 374 bp, 153 bp and 259 bp in length, respectively, and the corresponding sequences of O. columbianum were 259, 153 and 218 bp in length, respectively. Sequence differences in the ITS-1 and ITS-2 rDNA between the two Oesophagostomum species were 9.5–10.2% and 12.7–13.9%, respectively. Sequence differences in the ITS-1 and ITS-2 rDNA among members of the genus Oesophagostomum were 2.5–11.6% and 6.8–22.3%, respectively. Based on genetic markers in the ITS rDNA, an effective polymerase chain reaction (PCR) approach was developed to differentiate O. columbianum from O. asperum with a sensitivity of 0.2 ng/μl DNA. Since accurate characterization of parasites at different taxonomic levels is essential for population genetic studies and control of parasitosis, the present findings have important implications for studying epidemiology, taxonomy and population biology, as well as for the control of oesophagostomiasis.
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Bott NJ, Campbell BE, Beveridge I, Chilton NB, Rees D, Hunt PW, Gasser RB. A combined microscopic-molecular method for the diagnosis of strongylid infections in sheep. Int J Parasitol 2009; 39:1277-87. [PMID: 19328802 DOI: 10.1016/j.ijpara.2009.03.002] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2009] [Revised: 03/16/2009] [Accepted: 03/18/2009] [Indexed: 11/29/2022]
Abstract
We evaluated a combined microscopic-molecular approach for the diagnosis of key strongylid infections in sheep using panels of well-defined control and test samples. The method established is based on the separation of nematode eggs from faecal samples using a salt flotation procedure, the extraction and column-purification of genomic DNA, followed by real-time PCR and melting-curve analysis. Specific and semi-quantitative amplification from (a minimum of 0.1-2.0pg) genomic DNA of Haemonchus contortus, Teladorsagia circumcincta, Trichostrongylus spp., Cooperia oncophora, Oesophagostomum columbianum, Oesophagostomum venulosum or Chabertia ovina is achieved using a specific, forward oligonucleotide primer located in the second internal transcribed spacer (ITS-2) of nuclear ribosomal DNA (rDNA) together with a conserved reverse primer in the large subunit of rDNA. Using a panel of well-defined genomic DNA samples from eggs from sheep monospecifically infected with H. contortus or Te. circumcincta, there was a correlation between cycle threshold (Ct) values in the PCR and numbers of egg per gram of faeces, thus allowing the semi-quantitation of parasite DNA in faeces. The findings of the present study indicate that a microscopic-molecular approach provides a useful tool for diagnosis, for epidemiological and ecological surveys as well as for integration into parasite monitoring, drug resistance (i.e. 'egg count reduction') testing or control programmes, particularly following semi- or full-automation.
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Affiliation(s)
- Nathan J Bott
- Department of Veterinary Science, The University of Melbourne, 250 Princes Highway, Werribee, Vic. 3030, Australia
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Toward practical, DNA-based diagnostic methods for parasitic nematodes of livestock — Bionomic and biotechnological implications. Biotechnol Adv 2008; 26:325-34. [DOI: 10.1016/j.biotechadv.2008.03.003] [Citation(s) in RCA: 118] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2008] [Revised: 03/06/2008] [Accepted: 03/14/2008] [Indexed: 11/22/2022]
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Infectious and Parasitic Diseases of the Alimentary Tract. JUBB, KENNEDY & PALMER'S PATHOLOGY OF DOMESTIC ANIMALS 2007. [PMCID: PMC7155580 DOI: 10.1016/b978-070202823-6.50096-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
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Rishniw M, Barr SC, Simpson KW, Frongillo MF, Franz M, Dominguez Alpizar JL. Discrimination between six species of canine microfilariae by a single polymerase chain reaction. Vet Parasitol 2006; 135:303-14. [PMID: 16289566 DOI: 10.1016/j.vetpar.2005.10.013] [Citation(s) in RCA: 199] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2005] [Revised: 10/06/2005] [Accepted: 10/06/2005] [Indexed: 11/25/2022]
Abstract
Canine dirofilariasis caused by Dirofilaria immitis is usually diagnosed by specific antigen testing and/or identification of microfilariae. However, D. immitis and at least six other filariae can produce canine microfilaremias with negative heartworm antigen tests. Discriminating these can be of clinical importance. To resolve discordant diagnoses by two diagnostic laboratories in an antigen-negative, microfilaremic dog recently imported into the US from Europe we developed a simple molecular method of identifying different microfilariae, and subsequently validated our method against six different filariae known to infect dogs by amplifying ribosomal DNA spacer sequences by polymerase chain reaction using common and species-specific primers, and sequencing the products to confirm the genotype of the filariae. We identified the filaria in this dog as D. repens. This is the first case of D. repens infection in the United States. Additionally, we examined microfilariae from five additional antigen-negative, microfilaremic dogs and successfully identified the infecting parasite in each case. Our diagnoses differed from the initial morphological diagnosis in three of these cases, demonstrating the inaccuracy of morphological diagnosis. In each case, microfilariae identified morphologically as A. reconditum were identified as D. immitis by molecular methods. Finally, we demonstrated that our PCR method should amplify DNA from at least two additional filariae (Onchocerca and Mansonella), suggesting that this method may be suitable for genotyping all members of the family Onchocercidae.
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Affiliation(s)
- Mark Rishniw
- Department of Biomedical Sciences, Box 11, Veterinary Research Tower, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA.
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Chilton NB. The use of nuclear ribosomal DNA markers for the identification of bursate nematodes (order Strongylida) and for the diagnosis of infections. Anim Health Res Rev 2005; 5:173-87. [PMID: 15984323 DOI: 10.1079/ahr200497] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Many bursate nematodes are of major importance to animal health. Animals are often parasitized by multiple species that differ in their prevalence, relative abundance and/or pathogenicity. Implementation of effective management strategies for these parasites requires reliable methods for their detection in hosts, identification to the species level and measurement of intensity of infection. One major problem is the difficulty of accurately identifying and distinguishing many species of bursate nematode because of the remarkable morphological similarity of their eggs and larvae. The inability to identify, with confidence, individual nematodes (irrespective of their life-cycle stage) to the species level by morphological methods has often led to a search for species-specific genetic markers. Studies over the past 15 years have shown that sequences of the internal transcribed spacers of ribosomal DNA provide useful genetic markers, providing the basis for the development of PCR-based diagnostic tools. Such molecular methods represent powerful tools for studying the systematics, epidemiology and ecology of bursate nematodes and, importantly, for the specific diagnosis of infections in animals and humans, thus contributing to improved control and prevention strategies for these parasites.
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Affiliation(s)
- Neil B Chilton
- Department of Biology, University of Saskatchewan, 112 Science Place, Saskatoon, Saskatchewan S7N 5E2, Canada.
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Schindler AR, de Gruijter JM, Polderman AM, Gasser RB. Definition of genetic markers in nuclear ribosomal DNA for a neglected parasite of primates, Ternidens deminutus (Nematoda: Strongylida) – diagnostic and epidemiological implications. Parasitology 2005; 131:539-46. [PMID: 16174419 DOI: 10.1017/s0031182005007936] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2005] [Revised: 03/25/2005] [Accepted: 03/25/2005] [Indexed: 11/06/2022]
Abstract
Ternidens deminutus (Strongylida) is a parasitic nematode infecting non-human and human primates in parts of Africa, Asia and the Pacific islands. The present study genetically characterized T. deminutus and defined genetic markers in nuclear ribosomal DNA (rDNA) as a basis for developing molecular-diagnostic tools. The sequences of the second internal transcribed spacer (ITS-2) of rDNA were determined for adult specimens of T. deminutus (Nematoda: Strongylida: Oesophagostominae) from the Olive baboon and the Mona monkey. The length and G+C content of the ITS-2 sequences was 216 bp and approximately 43%, respectively. While there was no sequence variation among individual T. deminutus specimens from the baboon, 6 (2.8%) nucleotide differences were detected in the ITS-2 between the parasite from baboon and that of the Mona monkey, which is similar to the difference (3.2%) between 2 other species of Oesophagostominae (Oesophagostomum bifurcum and O. stephanostomum) from non-human primates, suggesting significant population variation or the existence of cryptic (i.e. hidden) species within T. deminutus . Pairwise comparisons of the ITS-2 sequences of the 2 operational taxonomic units of T. deminutus with previously published ITS-2 sequences for selected members of the subfamilies Oesophagostominae and Chabertiinae indicated that species from primates (including those representing the subgenera Conoweberia and Ihleia) are closely related, in accordance with previous morphological studies. The sequence differences (27-48.3%) in the ITS-2 between the 2 taxonomic units of T. deminutus and hookworms (superfamily Ancylostomatoidea) enabled their identification and delineation by polymerase chain reaction (PCR)-based mutation scanning. The genetic markers in the ITS-2 provide a foundation for improved, PCR-based diagnosis of T. deminutus infections and for investigating the life-cycle, transmission patterns and ecology of this parasite.
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Affiliation(s)
- A R Schindler
- Department of Veterinary Science, The University of Melbourne, 250 Princes Highway, Werribee, Victoria 3030, Australia
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Troell K, Mattsson JG, Alderborn A, Höglund J. Pyrosequencing analysis identifies discrete populations of Haemonchus contortus from small ruminants. Int J Parasitol 2003; 33:765-71. [PMID: 12814655 DOI: 10.1016/s0020-7519(03)00068-7] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The genus Haemonchus consists of blood-sucking parasitic nematodes in the abomasum of ruminants. Members of this genus are responsible for extensive production losses, particularly of small ruminants in the tropics but are also found in temperate regions. In this study, we examined the internal transcribed spacers-1 and -2 of rRNA in Haemonchus spp. The rRNA region spanning the internal transcribed spacers-1, -2 and the 5.8S rRNA gene was amplified by PCR from each of 10 worms from Swedish sheep, a Swedish goat and Kenyan sheep. The fragments were sequenced and examined with respect to genetic differences fixed among the three isolates. These and additional worms were further analysed with Pyrosequencing technology. This technique allowed us to rapidly analyse 110 individuals in three putative polymorphic nucleotide positions that were initially identified with dideoxy sequencing. The geographical isolates could to a large extent be genetically distinguished, but none of the polymorphic positions were consistent among all individuals within each isolate. Furthermore an alignment of our sequences and a consensus sequence published for Haemonchus contortus revealed two differences in positions 123 and 196 in internal transcribed spacers-2. Although these positions were previously reported as heterogenic, no polymorphism was detected among the 30 worms sequenced in the present study. Modelling of the internal transcribed spacers-2 secondary structure based on our data also identified a new putative long-range interaction. The isolates are best described as populations. In conclusion, consistent differences were not identified and the studied isolates are therefore best described as discrete populations. This study also reveals for the first time the potential of Pyrosequencing technology as a tool in the analysis of nematode population genetics.
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Affiliation(s)
- Karin Troell
- Department of Parasitology (SWEPAR), National Veterinary Institute, P.O. Box 7073, SE-751 89 Uppsala, Sweden
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19
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Chilton NB, Huby-Chilton F, Gasser RB, Beveridge I. Review of Papillostrongylus Johnston & Mawson, 1939 (Nematoda: Strongyloidea) from wallabies and kangaroos (Marsupialia: Macropodidae) using morphological and molecular techniques, with the description of P. barbatus n. sp. Syst Parasitol 2002; 51:81-93. [PMID: 11912337 DOI: 10.1023/a:1014062830560] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The strongyloid nematode genus Papillostrongylus Johnston & Mawson, 1939, from kangaroos and wallabies, is reviewed using morphological and molecular methods. P. labiatus Johnston & Mawson, 1939 is re-described from material from the type-host, the black-striped wallaby Macropus dorsalis, from eastern Queensland, Australia, in which it is a relatively common parasite. Additional records from M. parryi and Thylogale thetis are confirmed and considered to represent examples of host-switching. A geographically disjunct population of the nematode species occurs in M. bernardus and Petrogale brachyotis in Arnhem Land, Northern Territory, but assessment of its status requires additional material. Nematodes from M. rufus, M. giganteus, M. fuliginosus and M. robustus from inland regions of Australia, formerly attributed to P. labiatus, are here assigned to a new species, P. barbatus, distinguished by the presence of an external leaf-crown, larger size, by greater spicule length in the male and by a sinuous vagina in the female. Additional hosts of P. barbatus n. sp. are Petrogale assimilis and Pet. lateralis purpureicollis. Sequence analyses of the second internal transcribed spacer of ribosomal DNA (ITS-2) also showed that P. barbatus n. sp. differed at 40 (16.7%) of the 240 alignment positions when compared with P. labiatus. Most of these interspecific sequence differences occurred in loops or bulges of the predicted precursor rRNA secondary structure, or represented partial or total compenstory base pair changes in stems.
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Affiliation(s)
- N B Chilton
- Department of Veterinary Science, University of Melbourne, Parkville, Victoria, 3052, Australia
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20
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Gasser RB, Chilton NB. Applications of single-strand conformation polymorphism (SSCP) to taxonomy, diagnosis, population genetics and molecular evolution of parasitic nematodes. Vet Parasitol 2001; 101:201-13. [PMID: 11707297 DOI: 10.1016/s0304-4017(01)00567-2] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The analysis of genetic variation in parasitic nematodes has important implications for studying aspects of taxonomy, diagnosis, population genetics, drug resistance and molecular evolution. This article highlights some applications of PCR-based single-strand conformation polymorphism (SSCP) for the analysis of sequence variation in individual parasites (and their populations) to address some of these areas. It also describes the principles and advantages of SSCP, and provides some examples for future applications in parasitology.
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Affiliation(s)
- R B Gasser
- Department of Veterinary Science, The University of Melbourne, 250 Princes Highway, Werribee, Victoria 3030, Australia.
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21
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Gouÿ de Bellocq J, Ferté H, Depaquit J, Justine JL, Tillier A, Durette-Desset MC. Phylogeny of the Trichostrongylina (Nematoda) inferred from 28S rDNA sequences. Mol Phylogenet Evol 2001; 19:430-42. [PMID: 11399151 DOI: 10.1006/mpev.2001.0925] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We produced a molecular phylogeny of species within the order Strongylida (bursate nematodes) using the D1 and D2 domains of 28S rDNA, with 23 new sequences for each domain. A first analysis using Caenorhabditis elegans as an outgroup produced a tree with low resolution in which three taxa (Dictyocaulus filaria, Dictyocaulus noerneri, and Metastrongylus pudendotectus) showed highly divergent sequences. In a second analysis, these three species and C. elegans were removed and an Ancylostomatina, Bunostomum trigonocephalum, was chosen (on the basis of previous morphological analyses) as the outgroup for an analysis of the phylogenetic relationships between and within the Strongylina (strongyles) and Trichostrongylina (trichostrongyles). A very robust tree was obtained. The Trichostrongylina were monophyletic, but the Strongylina were paraphyletic, though this requires confirmation. Within the Trichostrongylina, the three superfamilies defined from morphological characters are confirmed, with the Trichostrongyloidea sister group to a clade including the Molineoidea and Heligmosomoidea. Within the Trichostrongyloidea, the Cooperiidae, Trichostrongylidae, and Haemonchidae were polytomous, the Haemonchinae were monophyletic, but the Ostertagiinae were paraphyletic. The sister-group relationships between Molineoidea and Heligmosomoidea were unsuspected from previous morphological analysis. No unequivocal morphological synapomorphy could be found for the grouping Molineoidea + Heligmosomoidea, but none was found which contradicted it.
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Affiliation(s)
- J Gouÿ de Bellocq
- Laboratoire de Biologie Parasitaire, Protistologie, et Helminthologie, Muséum National d'Histoire Naturelle, 61 Rue Buffon, Paris Cedex 05, 75231, France
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22
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Chilton NB, Newton LA, Beveridge I, Gasser RB. Evolutionary relationships of trichostrongyloid nematodes (Strongylida) inferred from ribosomal DNA sequence data. Mol Phylogenet Evol 2001; 19:367-86. [PMID: 11399147 DOI: 10.1006/mpev.2001.0938] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The evolutionary relationships of 21 species of trichostrongyloid nematodes were determined by use of sequence data of the second internal transcribed spacer of the ribosomal DNA aligned according to secondary structure information. Irrespective of the method of analysis used, the topologies of the phylogenetic trees derived from the molecular data differed with respect to all four hypotheses proposed previously for the evolutionary relationships of the different subfamilies within the Trichostrongylidae based on morphological data. Thus, the molecular data set did not resolve the conflict between the four previous proposals for the subfamilial relationships. Nonetheless, all trees derived from the molecular data showed strong support for the exclusion of the genera Filarinema and Amidostomum from the clade containing the species within the family Trichostrongylidae. This represents a major difference from the most recent proposal of the systematics of the Trichostrongyloidea in which these two genera were included within the Trichostrongylidae. Therefore, the molecular data support an earlier systematic framework in which Filarinema and Amidostomum were considered to be sister groups of the Trichostrongyloidea.
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MESH Headings
- Animals
- Base Sequence
- DNA, Helminth/chemistry
- DNA, Helminth/genetics
- DNA, Ribosomal/chemistry
- DNA, Ribosomal/genetics
- DNA, Ribosomal Spacer/genetics
- Evolution, Molecular
- Molecular Sequence Data
- Nucleic Acid Conformation
- Phylogeny
- RNA, Ribosomal/chemistry
- RNA, Ribosomal/genetics
- Sequence Alignment
- Sequence Analysis, DNA
- Sequence Homology, Nucleic Acid
- Trichostrongyloidea/classification
- Trichostrongyloidea/genetics
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Affiliation(s)
- N B Chilton
- Department of Veterinary Science, University of Melbourne, 250 Princes Highway, Werribee, Victoria, 3030, Australia
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23
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Morales-Hojas R, Post RJ, Shelley AJ, Maia-Herzog M, Coscarón S, Cheke RA. Characterisation of nuclear ribosomal DNA sequences from Onchocerca volvulus and Mansonella ozzardi (Nematoda: Filarioidea) and development of a PCR-based method for their detection in skin biopsies. Int J Parasitol 2001; 31:169-77. [PMID: 11239937 DOI: 10.1016/s0020-7519(00)00156-9] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
The internal transcribed spacer region (ITS1, 5.8S gene and ITS2) of the two filarial nematodes Onchocerca volvulus and Mansonella ozzardi was sequenced, and two species-specific primers designed in the ITS2 to develop a PCR-based method for their specific detection and differentiation. When used with a universal reverse primer, the two species-specific primers gave amplification products of different size, which were readily separated in an agarose gel. The PCR was tested on skin biopsies from 51 people from three localities in Brazil where M. ozzardi is present, and results have been compared with those of parasitological examination of blood. The species-specific PCR gave a higher percentage of detection of infection by M. ozzardi than the parasitological examination of blood. No infection with O. volvulus was detected by PCR. This PCR-based assay may assist in determining the nature of infection in areas where both filarial species exist in sympatry.
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Affiliation(s)
- R Morales-Hojas
- Department of Entomology, The Natural History Museum, Cromwell Road, SW7 5BD, London, UK.
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24
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Audebert F, Durette-Desset MC, Chilton NB. Internal transcribed spacer rDNA can be used to infer the phylogenetic relationships of species within the genus Nematodirus (Nematoda: molineoidea). Int J Parasitol 2000; 30:187-91. [PMID: 10704601 DOI: 10.1016/s0020-7519(99)00179-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Sequences of the first internal transcribed spacer rDNA were characterised for four veterinary important species of gastrointestinal nematodes from the genus Nematodirus. The sequence data were combined with previously published data of the second internal transcribed spacer to determine whether these rDNA regions provided a suitable number of informative characters to determine the phylogenetic relationships of species within the genus. A total of 32 alignment positions of the first internal transcribed spacer data set and 33 characters from the second internal transcribed spacer data set were informative in phylogenetic analyses. Irrespective of whether the data from each spacer were analysed separately or combined, only one most parsimonious tree was produced, with the relationships of the four species fully resolved. In addition, several regions of conservatism in the first internal transcribed spacer sequence among the four Nematodirus species suggests that this rDNA region may also provide phylogenetic information for higher taxonomic levels within the Molineoidea.
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Affiliation(s)
- F Audebert
- Muséum National d'Histoire Naturelle, Laboratoire de Biologie Parasitaire, 61 rue Buffon, 75231, Paris, France
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25
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Conole JC, Chilton NB, Järvis T, Gasser RB. Intraspecific and interspecific variation in the second internal transcribed spacer (ITS-2) sequence for Metastrongylus (Nematoda: Metastrongyloidea) detected by high resolution PCR-RFLP. Int J Parasitol 1999; 29:1935-40. [PMID: 10961849 DOI: 10.1016/s0020-7519(99)00149-6] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Metastrongylus species are important parasites of free-range pigs and wild boar, but little is known about the genetic make-up of natural populations. This study was undertaken to examine sequence variation in the internal transcribed spacer 2 of ribosomal DNA within and among three species of Metastrongylus using PCR-linked restriction fragment length polymorphism analysis. In contrast to many other species of bursate nematodes, significant intraspecific variation was detected in restriction fragment length polymorphism profiles among individual worms. In spite of this, it was possible to identify the three species by their distinctive restriction profiles. The findings suggest that the internal transcribed spacer 2 region should be useful for analysing population variation within Metastrongylus species.
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Affiliation(s)
- J C Conole
- Department of Veterinary Science, The University of Melbourne, Werribee, Victoria, Australia
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26
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Abstract
DNA technology is having a major impact in many areas of veterinary parasitology. In particular, the polymerase chain reaction (PCR) has found broad applicability because its sensitivity permits enzymatic amplification of gene fragments from minute quantities of nucleic acids derived from limited amounts of parasite material. This paper discusses some recent applications of PCR-based methods to parasites and highlights their usefulness or potential for those of veterinary importance. The focus is on PCR tools for the accurate identification of parasites and their genetic characterisation, the diagnosis of infections, the isolation and characterisation of expressed genes, the detection of anthelmintic resistance, and mutation scanning approaches for the high resolution analysis of PCR products.
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MESH Headings
- Animals
- DNA, Helminth/analysis
- DNA, Helminth/chemistry
- DNA, Protozoan/analysis
- DNA, Protozoan/chemistry
- Drug Resistance
- Eukaryota/classification
- Eukaryota/genetics
- Eukaryota/isolation & purification
- Expressed Sequence Tags
- Helminthiasis, Animal/diagnosis
- Helminths/classification
- Helminths/genetics
- Helminths/isolation & purification
- Microsatellite Repeats
- Parasitic Diseases, Animal/diagnosis
- Parasitic Diseases, Animal/therapy
- Polymerase Chain Reaction/methods
- Polymerase Chain Reaction/veterinary
- Polymorphism, Restriction Fragment Length
- Polymorphism, Single-Stranded Conformational
- Protozoan Infections, Animal/diagnosis
- Random Amplified Polymorphic DNA Technique/veterinary
- Sequence Analysis, DNA/veterinary
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Affiliation(s)
- R B Gasser
- Department of Veterinary Science, The University of Melbourne, Werribee, Victoria, Australia.
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27
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Gasser RB, Woods WG, Huffman MA, Blotkamp J, Polderman AM. Molecular separation of Oesophagostomum stephanostomum and Oesophagostomum bifurcum (Nematoda: Strongyloidea) from non-human primates. Int J Parasitol 1999; 29:1087-91. [PMID: 10501618 DOI: 10.1016/s0020-7519(99)00037-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The ITS-2 sequences for adult specimens of Oesophagostomum stephanostomum from the common chimpanzee and Oesophagostomum bifurcum from the Mona monkey were determined. For both species, the length and GC content of the ITS-2 sequences were 216 bp and 43%, respectively. While there was no unequivocal sequence difference among individual worms representing each of the two species, five (2.3%) interspecific nucleotide differences were detected. These differences were associated with the presence of unique restriction sites in the ITS-2 sequence of 0. stephanostomum for multiple endonucleases of diagnostic value for the differentiation of the two taxa by restriction analysis. Pairwise comparisons of the ITS-2 sequences of O. stephanostomum and O. bifurcum with published ITS-2 sequences for five different congeners indicated that these species from the subgenus Conoweberia are closely related, in accordance with previous morphological studies.
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Affiliation(s)
- R B Gasser
- Department of Veterinary Science, The University of Melbourne, Werribee, Victoria, Australia.
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28
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Gasser RB, Woods WG, Blotkamp C, Verweij J, Storey PA, Polderman AM. Screening for nucleotide variations in ribosomal DNA arrays of Oesophagostomum bifurcum by polymerase chain reaction-coupled single-strand conformation polymorphism. Electrophoresis 1999; 20:1486-91. [PMID: 10424472 DOI: 10.1002/(sici)1522-2683(19990601)20:7<1486::aid-elps1486>3.0.co;2-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
We exploited the high resolution capacity of polymerase chain reaction (PCR)-coupled single-strand conformation polymorphism (SSCP) to screen for sequence variation in the second internal transcribed spacer (ITS-2) of ribosomal DNA (rDNA) among 77 individuals representing Oesophagostumum bifurcum from human or Mona monkey hosts from Africa. SSCP analysis revealed distinct profiles among some of the individuals, and sequence analysis of representative samples defined different ITS-2 sequence types attributable to polymorphism at particular nucleotide positions. However, there was no unequivocal sequence difference between O. bifurcum individuals from humans and that from monkeys. This provided some support for the hypothesis that the parasite from the two hosts represents a single species and that the sequence microheterogeneity detected in the ITS-2 rDNA region represents population variation, although the findings were insufficient to reject the proposal that the parasite represents different species. Overall, the results showed the usefulness of the SSCP-sequencing approach for studying the genetic variation in O. bifurcum populations and indicated its potential to study macromolecular evolution and elucidate population differentiation at the molecular level.
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Affiliation(s)
- R B Gasser
- Department of Veterinary Science, The University of Melbourne, Werribee, Victoria, Australia.
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