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Home / Equine Research Bank / Vet Parasitol / Sequence heterogeneity in the 18S rRNA gene within Theileria...
Veterinary parasitology2008; 159(2); 112-120; doi: 10.1016/j.vetpar.2008.10.004

Sequence heterogeneity in the 18S rRNA gene within Theileria equi and Babesia caballi from horses in South Africa.

Abstract: A molecular epidemiological survey of the protozoal parasites that cause equine piroplasmosis was conducted using samples collected from horses and zebra from different geographical locations in South Africa. A total of 488 samples were tested for the presence of Theileria equi and/or Babesia caballi using the reverse line blot hybridization assay. Ten percent of the samples hybridized to the Theileria/Babesia genus-specific probe and not to the B. caballi or T. equi species-specific probes, suggesting the presence of a novel species or genotype. The small subunit of rRNA gene (18S; approximately 1600bp) was amplified and sequenced from 33 of these 488 samples. Sequences were compared with published sequences from the public sequence databases. Twelve distinct T. equi and six B. caballi 18S rRNA sequences were identified. Alignments demonstrated extensive sequence variation in the V4 hypervariable region of the 18S rRNA gene within T. equi. Sequence variation was also found in B. caballi 18S rRNA genes, although there was less variation than observed for T. equi. Phylogenetic analysis based on 18S rRNA gene sequences revealed three T. equi clades and two B. caballi clades in South Africa. The extent of sequence heterogeneity detected within T. equi and B. caballi 18S rRNA genes was unexpected since concerted evolution is thought to maintain homogeneity within repeated gene families, including rRNA genes, in eukaryotes. The findings reported here show that careful examination of variants of the 18S rRNA gene of T. equi and B. caballi is required prior to the development of molecular diagnostic tests to detect these parasites in horses. Species-specific probes must be in designed in regions of the gene that are both conserved within and unique to each species.
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Publication Date: 2008-10-11 PubMed ID: 19019541DOI: 10.1016/j.vetpar.2008.10.004Google Scholar: Lookup
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  • Non-U.S. Gov't

Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

This research study investigates the genetic diversity within two parasites known to cause equine piroplasmosis, using horses and zebras in South Africa as test subjects. The surprising range of genetic variation discovered among the rRNA genes of these parasites may lead to the development of more effective molecular diagnostic tests.

Study Methodology

  • The researchers carried out a survey of the parasites causing equine piroplasmosis by collecting and assessing 488 sample specimens from horses and zebras in various regions in South Africa.
  • The reverse line blot hybridization assay was used to test for the presence of Theileria equi and/or Babesia caballi, the protozoal parasites responsible for the disease.
  • They observed that 10% of the samples reacted with a generic probe for Theileria/Babesia genus but not to the specific probes for T. equi or B. caballi, implying the possibility of a novel species or genotype.
  • The 18S rRNA gene, known to be present and conserved in most organisms, was targeted and sequenced from 33 of these samples.

Findings

  • In comparing the identified sequences to published sequence databases, there were 12 distinct T. equi and six B. caballi 18S rRNA sequences found.
  • Significant sequence differences were observed in the V4 hypervariable region of the 18S rRNA gene of T. equi.
  • While variation was also found in the B. caballi 18S rRNA genes, the extent of this was less than that seen in T. equi.
  • Three T. equi clades (genetically related group of organisms) and two B. caballi clades were identified in South Africa through a phylogenetic analysis of these 18S rRNA gene sequences.

Implications

  • Eukaryotes mostly maintain uniformity within their repeated gene families, including rRNA genes, through a process known as concerted evolution. As such, the observed level of heterogeneity (diversity) within the rRNA genes of T. equi and B. caballi was unexpected.
  • The study indicates that careful examination of the gene variants in these parasites is necessary for accurately developing molecular diagnostic tests to detect these organisms in horses.
  • Species-specific probes that account for this genetic diversity, and that are focused on parts of the gene uniform within but unique to each species, will need to be designed to enhance diagnostic accuracy.

Cite This Article

APA
Bhoora R, Franssen L, Oosthuizen MC, Guthrie AJ, Zweygarth E, Penzhorn BL, Jongejan F, Collins NE. (2008). Sequence heterogeneity in the 18S rRNA gene within Theileria equi and Babesia caballi from horses in South Africa. Vet Parasitol, 159(2), 112-120. https://doi.org/10.1016/j.vetpar.2008.10.004

Publication

Veterinary parasitology
ISSN: 0304-4017
NlmUniqueID: 7602745
Country: Netherlands
Language: English
Volume: 159
Issue: 2
Pages: 112-120

Researcher Affiliations

Bhoora, Raksha
  • Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort 0110, South Africa. raksha.bhoora@up.ac.za
Franssen, Linda
    Oosthuizen, Marinda C
      Guthrie, Alan J
        Zweygarth, Erich
          Penzhorn, Barend L
            Jongejan, Frans
              Collins, Nicola E

                MeSH Terms

                • Animals
                • Babesia / genetics
                • Babesiosis / epidemiology
                • Babesiosis / parasitology
                • Babesiosis / veterinary
                • Base Sequence
                • Genetic Variation
                • Horse Diseases / epidemiology
                • Horse Diseases / parasitology
                • Horses
                • Molecular Sequence Data
                • Phylogeny
                • RNA, Ribosomal, 18S / genetics
                • South Africa / epidemiology
                • Theileria / genetics
                • Theileriasis / epidemiology
                • Theileriasis / parasitology

                Citations

                This article has been cited 36 times.
                1. Ochi A, Kidaka T, Hakimi H, Asada M, Yamagishi J. Chromosome-level genome assembly of Babesia caballi reveals diversity of multigene families among Babesia species.. BMC Genomics 2023 Aug 24;24(1):483.
                  doi: 10.1186/s12864-023-09540-wpubmed: 37620766google scholar: lookup
                2. Coultous R, Gotić J, McCann M, Sutton D, Beck R, Shiels B. Novel equi merozoite antigen (ema-1) gene heterogeneity in a geographically isolated Theileria equi population in Croatia.. Parasit Vectors 2022 Oct 31;15(1):401.
                  doi: 10.1186/s13071-022-05484-4pubmed: 36316753google scholar: lookup
                3. Ledwaba MB, Nozipho K, Tembe D, Onyiche TE, Chaisi ME. Distribution and prevalence of ticks and tick-borne pathogens of wild animals in South Africa: A systematic review.. Curr Res Parasitol Vector Borne Dis 2022;2:100088.
                  doi: 10.1016/j.crpvbd.2022.100088pubmed: 35601607google scholar: lookup
                4. Schnittger L, Ganzinelli S, Bhoora R, Omondi D, Nijhof AM, Florin-Christensen M. The Piroplasmida Babesia, Cytauxzoon, and Theileria in farm and companion animals: species compilation, molecular phylogeny, and evolutionary insights.. Parasitol Res 2022 May;121(5):1207-1245.
                  doi: 10.1007/s00436-022-07424-8pubmed: 35098377google scholar: lookup
                5. Elsawy BSM, Nassar AM, Alzan HF, Bhoora RV, Ozubek S, Mahmoud MS, Kandil OM, Mahdy OA. Rapid Detection of Equine Piroplasms Using Multiplex PCR and First Genetic Characterization of Theileria haneyi in Egypt.. Pathogens 2021 Oct 31;10(11).
                  doi: 10.3390/pathogens10111414pubmed: 34832570google scholar: lookup
                6. Torres R, Hurtado C, Pérez-Macchi S, Bittencourt P, Freschi C, de Mello VVC, Machado RZ, André MR, Müller A. Occurrence and Genetic Diversity of Babesia caballi and Theileria equi in Chilean Thoroughbred Racing Horses.. Pathogens 2021 Jun 7;10(6).
                  doi: 10.3390/pathogens10060714pubmed: 34200433google scholar: lookup
                7. Dirks E, de Heus P, Joachim A, Cavalleri JV, Schwendenwein I, Melchert M, Fuehrer HP. First Case of Autochthonous Equine Theileriosis in Austria.. Pathogens 2021 Mar 4;10(3).
                  doi: 10.3390/pathogens10030298pubmed: 33806575google scholar: lookup
                8. Ghafar A, Koehler AV, Hall RS, Gauci CG, Gasser RB, Jabbar A. Targeted Next-Generation Sequencing and Informatics as an Effective Tool to Establish the Composition of Bovine Piroplasm Populations in Endemic Regions.. Microorganisms 2020 Dec 23;9(1).
                  doi: 10.3390/microorganisms9010021pubmed: 33374586google scholar: lookup
                9. Adelabu OA, Iweriebor BC, Okoh AI, Obi LC. Genomic Profiling for Piroplasms in Feeding Ixodid Ticks in the Eastern Cape, South Africa.. Pathogens 2020 Dec 18;9(12).
                  doi: 10.3390/pathogens9121061pubmed: 33353073google scholar: lookup
                10. Tirosh-Levy S, Gottlieb Y, Fry LM, Knowles DP, Steinman A. Twenty Years of Equine Piroplasmosis Research: Global Distribution, Molecular Diagnosis, and Phylogeny.. Pathogens 2020 Nov 8;9(11).
                  doi: 10.3390/pathogens9110926pubmed: 33171698google scholar: lookup
                11. Mshelia PW, Kappmeyer L, Johnson WC, Kudi CA, Oluyinka OO, Balogun EO, Richard EE, Onoja E, Sears KP, Ueti MW. Molecular detection of Theileria species and Babesia caballi from horses in Nigeria.. Parasitol Res 2020 Sep;119(9):2955-2963.
                  doi: 10.1007/s00436-020-06797-ypubmed: 32647992google scholar: lookup
                12. Tirosh-Levy S, Steinman A, Levy H, Katz Y, Shtilman M, Gottlieb Y. Parasite load and genotype are associated with clinical outcome of piroplasm-infected equines in Israel.. Parasit Vectors 2020 May 20;13(1):267.
                  doi: 10.1186/s13071-020-04133-ypubmed: 32434550google scholar: lookup
                13. Tirosh-Levy S, Gottlieb Y, Mimoun L, Mazuz ML, Steinman A. Transplacental Transmission of Theileria equi Is Not a Common Cause of Abortions and Infection of Foals in Israel.. Animals (Basel) 2020 Feb 21;10(2).
                  doi: 10.3390/ani10020341pubmed: 32098113google scholar: lookup
                14. Sunday Idoko I, Tirosh-Levy S, Leszkowicz Mazuz M, Mohammed Adam B, Sikiti Garba B, Wesley Nafarnda D, Steinman A. Genetic Characterization of Piroplasms in Donkeys and Horses from Nigeria.. Animals (Basel) 2020 Feb 18;10(2).
                  doi: 10.3390/ani10020324pubmed: 32085574google scholar: lookup
                15. Del Campo J, Heger TJ, Rodríguez-Martínez R, Worden AZ, Richards TA, Massana R, Keeling PJ. Assessing the Diversity and Distribution of Apicomplexans in Host and Free-Living Environments Using High-Throughput Amplicon Data and a Phylogenetically Informed Reference Framework.. Front Microbiol 2019;10:2373.
                  doi: 10.3389/fmicb.2019.02373pubmed: 31708883google scholar: lookup
                16. Sant C, Allicock OM, d'Abadie R, Charles RA, Georges K. Phylogenetic analysis of Theileria equi and Babesia caballi sequences from thoroughbred mares and foals in Trinidad.. Parasitol Res 2019 Apr;118(4):1171-1177.
                  doi: 10.1007/s00436-019-06240-xpubmed: 30761425google scholar: lookup
                17. Díaz-Sánchez AA, Pires MS, Estrada CY, Cañizares EV, Del Castillo Domínguez SL, Cabezas-Cruz A, Rivero EL, da Fonseca AH, Massard CL, Corona-González B. First molecular evidence of Babesia caballi and Theileria equi infections in horses in Cuba.. Parasitol Res 2018 Oct;117(10):3109-3118.
                  doi: 10.1007/s00436-018-6005-5pubmed: 30033488google scholar: lookup
                18. Lobanov VA, Peckle M, Massard CL, Brad Scandrett W, Gajadhar AA. Development and validation of a duplex real-time PCR assay for the diagnosis of equine piroplasmosis.. Parasit Vectors 2018 Mar 2;11(1):125.
                  doi: 10.1186/s13071-018-2751-6pubmed: 29499748google scholar: lookup
                19. Montes-Cortés MG, Fernández-García JL, Martínez-Estéllez MÁH. Genetic Variation of the β-tubulin Gene of Babesia caballi Strains.. J Arthropod Borne Dis 2017 Sep;11(3):344-353.
                  pubmed: 29322051
                20. Hailemariam Z, Krücken J, Baumann M, Ahmed JS, Clausen PH, Nijhof AM. Molecular detection of tick-borne pathogens in cattle from Southwestern Ethiopia.. PLoS One 2017;12(11):e0188248.
                  doi: 10.1371/journal.pone.0188248pubmed: 29155863google scholar: lookup
                21. He L, Miao X, Hu J, Huang Y, He P, He J, Yu L, Malobi N, Shi L, Zhao J. First Molecular Detection of Babesia gibsoni in Dogs from Wuhan, China.. Front Microbiol 2017;8:1577.
                  doi: 10.3389/fmicb.2017.01577pubmed: 28871243google scholar: lookup
                22. Montes Cortés MG, Fernández-García JL, Habela Martínez-Estéllez MÁ. Seroprevalence of Theileria equi and Babesia caballi in horses in Spain.. Parasite 2017;24:14.
                  doi: 10.1051/parasite/2017015pubmed: 28497743google scholar: lookup
                23. Chaisi ME, Baxter JR, Hove P, Choopa CN, Oosthuizen MC, Brayton KA, Khumalo ZT, Mutshembele AM, Mtshali MS, Collins NE. Comparison of three nucleic acid-based tests for detecting Anaplasma marginale and Anaplasma centrale in cattle.. Onderstepoort J Vet Res 2017 Jan 23;84(1):e1-e9.
                  doi: 10.4102/ojvr.v84i1.1262pubmed: 28155283google scholar: lookup
                24. Ogedengbe JD, Ogedengbe ME, Hafeez MA, Barta JR. Molecular phylogenetics of eimeriid coccidia (Eimeriidae, Eimeriorina, Apicomplexa, Alveolata): A preliminary multi-gene and multi-genome approach.. Parasitol Res 2015 Nov;114(11):4149-60.
                  doi: 10.1007/s00436-015-4646-1pubmed: 26319519google scholar: lookup
                25. Gjerde B, Hilali M, Mawgood SA. Molecular characterisation of three regions of the nuclear ribosomal DNA unit and the mitochondrial cox1 gene of Sarcocystis fusiformis from water buffaloes (Bubalus bubalis) in Egypt.. Parasitol Res 2015 Sep;114(9):3401-13.
                  doi: 10.1007/s00436-015-4566-0pubmed: 26051128google scholar: lookup
                26. Mans BJ, Pienaar R, Latif AA. A review of Theileria diagnostics and epidemiology.. Int J Parasitol Parasites Wildl 2015 Apr;4(1):104-18.
                  doi: 10.1016/j.ijppaw.2014.12.006pubmed: 25830110google scholar: lookup
                27. Stenger BL, Clark ME, Kváč M, Khan E, Giddings CW, Dyer NW, Schultz JL, McEvoy JM. Highly divergent 18S rRNA gene paralogs in a Cryptosporidium genotype from eastern chipmunks (Tamias striatus).. Infect Genet Evol 2015 Jun;32:113-23.
                  doi: 10.1016/j.meegid.2015.03.003pubmed: 25772204google scholar: lookup
                28. Adamu M, Troskie M, Oshadu DO, Malatji DP, Penzhorn BL, Matjila PT. Occurrence of tick-transmitted pathogens in dogs in Jos, Plateau State, Nigeria.. Parasit Vectors 2014 Mar 24;7:119.
                  doi: 10.1186/1756-3305-7-119pubmed: 24661795google scholar: lookup
                29. Chaisi ME, Janssens ME, Vermeiren L, Oosthuizen MC, Collins NE, Geysen D. Evaluation of a real-time PCR test for the detection and discrimination of theileria species in the African buffalo (Syncerus caffer).. PLoS One 2013;8(10):e75827.
                  doi: 10.1371/journal.pone.0075827pubmed: 24146782google scholar: lookup
                30. Salim B, Bakheit MA, Sugimoto C. Rapid detection and identification of Theileria equi and Babesia caballi by high-resolution melting (HRM) analysis.. Parasitol Res 2013 Nov;112(11):3883-6.
                  doi: 10.1007/s00436-013-3581-2pubmed: 23990047google scholar: lookup
                31. Estrada-Peña A, Gray JS, Kahl O, Lane RS, Nijhof AM. Research on the ecology of ticks and tick-borne pathogens--methodological principles and caveats.. Front Cell Infect Microbiol 2013;3:29.
                  doi: 10.3389/fcimb.2013.00029pubmed: 23964348google scholar: lookup
                32. Zulfiqar S, Shahnawaz S, Ali M, Bhutta AM, Iqbal S, Hayat S, Qadir S, Latif M, Kiran N, Saeed A, Ali M, Iqbal F. Detection of Babesia bovis in blood samples and its effect on the hematological and serum biochemical profile in large ruminants from Southern Punjab.. Asian Pac J Trop Biomed 2012 Feb;2(2):104-8.
                  doi: 10.1016/S2221-1691(11)60202-5pubmed: 23569878google scholar: lookup
                33. Hall CM, Busch JD, Scoles GA, Palma-Cagle KA, Ueti MW, Kappmeyer LS, Wagner DM. Genetic characterization of Theileria equi infecting horses in North America: evidence for a limited source of U.S. introductions.. Parasit Vectors 2013 Feb 11;6:35.
                  doi: 10.1186/1756-3305-6-35pubmed: 23399005google scholar: lookup
                34. Khattak RM, Rabib M, Khan Z, Ishaq M, Hameed H, Taqddus A, Faryal M, Durranis S, Gillani QU, Allahyar R, Shaikh RS, Khan MA, Ali M, Iqbal F. A comparison of two different techniques for the detection of blood parasite, Theileria annulata, in cattle from two districts in Khyber Pukhtoon Khwa Province (Pakistan).. Parasite 2012 Feb;19(1):91-5.
                  doi: 10.1051/parasite/2012191091pubmed: 22314246google scholar: lookup
                35. Shahnawaz S, Ali M, Aslam MA, Fatima R, Chaudhry ZI, Hassan MU, Ali M, Iqbal F. A study on the prevalence of a tick-transmitted pathogen, Theileria annulata, and hematological profile of cattle from Southern Punjab (Pakistan).. Parasitol Res 2011 Oct;109(4):1155-60.
                  doi: 10.1007/s00436-011-2360-1pubmed: 21451992google scholar: lookup
                36. Salim B, Bakheit MA, Kamau J, Nakamura I, Sugimoto C. Nucleotide sequence heterogeneity in the small subunit ribosomal RNA gene within Theileria equi from horses in Sudan.. Parasitol Res 2010 Jan;106(2):493-8.
                  doi: 10.1007/s00436-009-1691-7pubmed: 19953269google scholar: lookup
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