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Heuristic Mining of Hierarchical Genotypes and Accessory Genome Loci in Bacterial Populations
Published on: December 7, 2021
Genotyping Giardia duodenalis isolates from dogs: lessons from a multilocus sequence typing study.
Relja Beck1, Hein Sprong, Edoardo Pozio
1Department for Bacteriology and Parasitology, Croatian Veterinary Institute, Zagreb, Croatia.
Vector Borne and Zoonotic Diseases (Larchmont, N.Y.)
|October 26, 2011
Summary
Giardia duodenalis assemblages C and D are common in dogs, indicating a limited zoonotic role. Analyzing multiple genetic markers is crucial for accurate giardiasis diagnosis in dogs.
Area of Science:
- Veterinary Parasitology
- Molecular Epidemiology
- Microbial Genetics
Background:
- Giardiasis is a prevalent intestinal infection in dogs, caused by Giardia duodenalis.
- Both zoonotic and host-specific strains of Giardia duodenalis circulate in canine populations.
- Accurate identification of Giardia duodenalis assemblages is essential for understanding transmission dynamics.
Purpose of the Study:
- To analyze Giardia duodenalis isolates from Croatian dogs at four genetic loci.
- To determine the prevalence of different assemblages and assess potential zoonotic transmission.
- To evaluate the reliability of single-locus genotyping for characterizing Giardia duodenalis.
Main Methods:
- Genotyping of Giardia duodenalis isolates from 96 dogs (44 privately owned, 52 kennels) using ITS, gdh, tpi, and bg loci.
- Utilized generic and assemblage D-specific primers for tpi gene amplification.
- Phylogenetic analysis and assessment of genetic variability within assemblages.
Main Results:
- The tpi gene showed the highest amplification rate (85%) when using combined primers.
- Assemblages C and D were predominant in both kennel and household dogs, suggesting limited zoonotic potential.
- Incongruent results among markers in kennel dogs indicated mixed infections rather than recombination.
Conclusions:
- Canine Giardia duodenalis isolates are primarily composed of assemblages C and D, minimizing dogs' role in zoonotic transmission.
- Genotyping based on single markers can be unreliable, potentially misinterpreting mixed infections.
- The current typing scheme requires refinement to accurately differentiate mixed infections from genetic recombination in field isolates.
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