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Cited by 399

The DOI matches its Crossref record; 4 of the 4 references it cites were found in a registry or an index.

Recombination and clonal groupings within Helicobacter pylori from different geographical regions

Open access
Achtman, Mark, Azuma, Takeshi, Berg, Douglas E., Ito, Yoshiyuki, Morelli, Giovanna, Pan, Zhi‐Jun, Suerbaum, Sebastian, Thompson, Stuart A., Van Der Ende, Arie, Van Doorn, Leen‐Jan·1999·Molecular Microbiology

Abstract

A collection of 20 strains of Helicobacter pylori from several regions of the world was studied to better understand the population genetic structure and diversity of this species. Sequences of fragments from seven housekeeping genes (atpA, efp, mutY, ppa, trpC, ureI, yphC ) and two virulence‐associated genes (cagA, vacA) showed high levels of synonymous sequence variation (mean percentage Ks of 10–27%) and lower levels of non‐synonymous variation (mean percentage Ka of 0.2–5.6%). Cluster analysis of pairwise differences between alleles revealed the existence of two weakly clonal groupings, which included half of the strains investigated. All six strains isolated from Japanese and coastal Chinese were assigned to the ‘Asian’ clonal grouping, probably reflecting descent from a distinct common ancestor. The clonal groupings were not totally uniform; recombination, as measured by the homoplasy test and compatibility matrices, was extremely common within all genes tested, except cagA. The fact that clonal descent could still be discerned despite such frequent recombination possibly reflects founder effects and geographical separation and/or selection for particular alleles of these genes.

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Crossref · 10.1046/j.1365-2958.1999.01382.x

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Metadata

Authors
Achtman, M., Azuma, T., Berg, D. E., Ito, Y., Morelli, G., Pan, Z., Suerbaum, S., Thompson, S. A., Van Der Ende, A., & Van Doorn, L.
Venue
Molecular Microbiology
Publisher
Wiley
Published
1999-05
Volume
32
Issue
3
Pages
459-470
ISSN
  • 0950-382X (ISSN-L)
  • 1365-2958
OpenAlex
W1991369558
Cited by
399
References
4
FWCI
26.92
Type
journal article
Language
en
Open access
bronze

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CoChat. (2026). Citation check: Recombination and clonal groupings within Helicobacter pylori from different geographical regions. https://app.cochat.ai/papers/10.1046/j.1365-2958.1999.01382.x
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Achtman, M., Azuma, T., Berg, D. E., Ito, Y., Morelli, G., Pan, Z., Suerbaum, S., Thompson, S. A., Van Der Ende, A., & Van Doorn, L. (1999). Recombination and clonal groupings within Helicobacter pylori from different geographical regions. Molecular Microbiology. https://doi.org/10.1046/j.1365-2958.1999.01382.x

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