Evidence map›Paper›PMID 41326367›Full record

ArticleNature communications2025

Host range expansion of asexual parasite can be explained by loss of adaptions in Muller's Ratchet.

Swapnil Tichkule, Cock van Oosterhout, Simone M Cacciò, Filip Weisz, Balu Balan, Eva Nohýnková, Myo Naung, Brendan R E Ansell, Samantha J Emery-Corbin, Louise Baker and 4 more

Abstract read
In one paragraph

Article in Nature communications, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 2 papers.

0numbers the graph read from it
0cells of the map it votes in
2citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

2 citing papers in PubMed.

  1. Article
  2. Stuck on you Giardia.Nature microbiology · 2026
    Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

14 authors.

Swapnil TichkuleInfection and Global Health, Walter and Eliza Hall Institute, Parkville, VIC, Australia.ORCID http://orcid.org/0000-0003-2940-9961
Cock van OosterhoutSchool of Environmental Sciences, University of East Anglia, Norwich Research Park, Norwich, UK.ORCID http://orcid.org/0000-0002-5653-738X
Simone M CacciòDepartment of Infectious Diseases, Istituto Superiore di Sanità, Rome, Italy.
Filip WeiszInstitute of Medical Microbiology, First Faculty of Medicine, Charles University, Prague, Czech Republic.ORCID http://orcid.org/0000-0002-5398-765X
Balu BalanInfection and Global Health, Walter and Eliza Hall Institute, Parkville, VIC, Australia.
Eva NohýnkováInstitute of Medical Microbiology, First Faculty of Medicine, Charles University, Prague, Czech Republic.
Myo NaungInfection and Global Health, Walter and Eliza Hall Institute, Parkville, VIC, Australia.
Brendan R E AnsellInfection and Global Health, Walter and Eliza Hall Institute, Parkville, VIC, Australia.ORCID http://orcid.org/0000-0003-0297-897X
Samantha J Emery-CorbinInfection and Global Health, Walter and Eliza Hall Institute, Parkville, VIC, Australia.ORCID http://orcid.org/0000-0003-2984-0620
Louise BakerInfection and Global Health, Walter and Eliza Hall Institute, Parkville, VIC, Australia.
Marco LalleDepartment of Infectious Diseases, Istituto Superiore di Sanità, Rome, Italy.ORCID http://orcid.org/0000-0001-5168-2150
Staffan SvärdDepartment of Cell and Molecular Biology, Uppsala University, Uppsala, Sweden.
Robin B GasserMelbourne Veterinary School, University of Melbourne, Parkville, VIC, Australia.ORCID http://orcid.org/0000-0002-4423-1690
Aaron R JexInfection and Global Health, Walter and Eliza Hall Institute, Parkville, VIC, Australia. jex.a@wehi.edu.au.ORCID http://orcid.org/0000-0002-1285-7947

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Sexual recombination is a hallmark of eukaryotic evolution. Without recombination, asexual eukaryotes should succumb to deleterious mutations and more rapidly evolving pathogens. Giardia duodenalis, a parasitic protist, sits within one of the earliest-branching eukaryotic lineages and has no known sexual stage. Whether Giardia are 'ancient asexuals' has been long explored but is unresolved. Here, we find clear evidence of sex in Giardia and also discover an asexual sublineage that has a broader host range than its sexual ancestor. This asexual lineage is not ancient, and is accumulating deleterious mutations. Unlike its sexual counterparts, its genetic variation lacks the signatures of selection and Red Queen coevolution. We propose a new hypothesis that explains how a mutational meltdown during Muller's Ratchet might enable asexual pathogens to expand their host ranges transiently. Fittingly, our results suggest that Giardia is not the last exception to, but rather further evidence of, the essentiality of eukaryotic sex.

Indexed as

Giardia lambliaHost SpecificityReproduction, AsexualAnimalsBiological EvolutionGenetic VariationMutationParasitesPhylogeny

Identifiers

PMID41326367
PMCPMC12669663

What OpenQuestion holds

Textmetadata
LicenceCC BY-NC-ND
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.