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Heuristic Mining of Hierarchical Genotypes and Accessory Genome Loci in Bacterial Populations
Published on: December 7, 2021
Population-based analyses of Giardia duodenalis is consistent with the clonal assemblage structure
Katsuhisa Takumi1, Arno Swart, Theo Mank
1National Institute of Public Health and Environment (RIVM), Laboratory for Zoonosis and Environmental Microbiology (CIb-LZO), P.O. Box 1, 3720, BA, Bilthoven, The Netherlands.
Parasites & Vectors
|August 14, 2012
Summary
Recombination between Giardia duodenalis assemblages is rare or absent in natural populations. Analyses suggest clonal reproduction is more likely than inter-assemblage recombination in Giardia duodenalis.
Area of Science:
- Parasitology
- Population Genetics
- Molecular Biology
Background:
- Giardia duodenalis is a common protozoan parasite infecting humans and animals.
- Eight assemblages of G. duodenalis are known, differing in host specificity.
- Previous studies suggested recombination within and between assemblages, challenging clonal reproduction.
Purpose of the Study:
- To investigate the occurrence of recombination between Giardia duodenalis assemblages.
- To determine if observed genetic diversity results from recombination or multiple infections.
Main Methods:
- Population genetic analyses were performed on an extensive dataset of G. duodenalis isolates.
- Both single-locus and multi-locus data were analyzed.
- Statistical analyses were used to assess patterns of reproduction.
Main Results:
- Recombination events between different G. duodenalis assemblages appear to be rare or absent in natural populations.
- Multi-locus genetic data are more consistent with clonal reproduction.
- The presence of multiple G. duodenalis genotypes within a single host isolate can explain the observed genetic patterns.
Conclusions:
- Recombination between G. duodenalis assemblages is likely very rare or does not occur.
- Clonal reproduction is a significant mode of reproduction for G. duodenalis.
- Further research is needed on intra-assemblage recombination and nuclear exchange within cysts.
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