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Parasitology research2007; 101(5); 1215-1224; doi: 10.1007/s00436-007-0603-y

Population sub-structuring among Trypanosoma evansi stocks.

Abstract: To investigate the population genetic structure of Trypanosoma evansi from domesticated animals, we have analysed 112 stocks from camels, buffaloes, cattle and horses using the tandemly repeated coding sequence (MORF2) and minisatellite markers 292 and cysteine-rich acidic integral membrane protein (CRAM). We recorded a total of six alleles at the MORF2 locus, seven at 292 and 12 at the CRAM loci. Nei's genetic distance showed reduced allelic diversity between buffaloes and cattle stocks (1.2) as compared to the diversity between camels and buffaloes (3.75) and camels and cattle stock (1.69). The mean index of association (IA=0.92) significantly deviated from zero, and the average number of multilocus genotypes (G/N ratio) was 0.21. Twenty-four multilocus genotypes were defined from the combination of alleles at the three loci. The Kenyan sub-populations showed Fst=0.28 and analysis of molecular variance showed significant divergence (22.7%) between the Laikipia, Kulal and Galana regions. The regional and host distribution of multi-locus genotypes significant population differentiation and high Nei's genetic distances suggest existence of genetic sub-structuring within T. evansi stocks while the few multi-locus genotypes and deviation of association index from zero indicate the lack of recombination. In conclusion, this study reveals that some genetic sub-structuring does occur within T. evansi, which has a clonal population structure.
Publication Date: 2007-06-22 PubMed ID: 17587054DOI: 10.1007/s00436-007-0603-yGoogle Scholar: Lookup
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  • Journal Article
  • Research Support
  • 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.

The research article focuses on examining the genetic structure of Trypanosoma evansi, a parasite found in domesticated animals. Using different genetic markers, the research discovered varying degrees of genetic diversity among different animal hosts and geographical regions, suggesting that there is some genetic sub-structuring within this parasite population.

Methodology

  • The study analysed 112 stocks of Trypanosoma evansi from camels, buffaloes, cattle, and horses.
  • Researchers used the tandemly repeated coding sequence (MORF2) and minisatellite markers 292 and CRAM to study the genetic structure of the parasite populations.
  • Data from these genetic analyses were compared to discern patterns and degrees of genetic diversity among the parasites from different hosts and regions.

Results

  • There were six alleles found at the MORF2 locus, seven at 292, and 12 at the CRAM loci.
  • Nei’s genetic distance showed less allelic diversity between buffaloes and cattle stocks as compared to the diversity between camels and buffaloes and camels and cattle stocks.
  • The mean index of association significantly deviated from zero, suggesting a lack of recombination within the parasite population.
  • Twenty-four multilocus genotypes were defined from the combination of alleles at the three loci.

Analysis and Conclusion

  • The regional and host distribution of multilocus genotypes showed significant population differentiation, suggesting the existence of genetic sub-structuring within T. evansi stocks.
  • The Kenyan sub-populations showed an Fst value of 0.28, indicating genetic variance among subpopulations.
  • The study concluded that some genetic sub-structuring occurs within T. evansi, which appears to have a clonal population structure. This implies that the populations of the parasite can reproduce asexually, hence each new generation is genetically identical to the parent. This could potentially have implications for the management of diseases caused by T. evansi, as it might affect the effectiveness of treatment strategies.

Cite This Article

APA
Njiru ZK, Constantine CC. (2007). Population sub-structuring among Trypanosoma evansi stocks. Parasitol Res, 101(5), 1215-1224. https://doi.org/10.1007/s00436-007-0603-y

Publication

ISSN: 0932-0113
NlmUniqueID: 8703571
Country: Germany
Language: English
Volume: 101
Issue: 5
Pages: 1215-1224

Researcher Affiliations

Njiru, Z K
  • School of Nursing, Murdoch University, Carleton Place, 15-17, Mandurah, WA, 6150, Australia. z.njiru@murdoch.edu.au
Constantine, C C

    MeSH Terms

    • Alleles
    • Animals
    • Animals, Domestic / parasitology
    • Buffaloes / parasitology
    • Camelus / parasitology
    • Cattle / parasitology
    • Cluster Analysis
    • DNA, Protozoan / genetics
    • Horses / parasitology
    • Kenya
    • Minisatellite Repeats
    • Polymorphism, Genetic
    • Protozoan Proteins / genetics
    • Trypanosoma / classification
    • Trypanosoma / genetics
    • Trypanosoma / isolation & purification
    • Trypanosomiasis / parasitology
    • Trypanosomiasis / veterinary

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    Citations

    This article has been cited 5 times.
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