Free recombination within Helicobacter pylori.
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ABSTRACT:
SUBMITTER: Suerbaum S
PROVIDER: S-EPMC22880 | biostudies-literature | 1998 Oct
REPOSITORIES: biostudies-literature
Publications
Free recombination within Helicobacter pylori.
Suerbaum S S Smith J M JM Bapumia K K Morelli G G Smith N H NH Kunstmann E E Dyrek I I Achtman M M
Proceedings of the National Academy of Sciences of the United States of America 19981001 21
Sequences of three gene fragments (flaA, flaB, and vacA) from Helicobacter pylori strains isolated from patients in Germany, Canada, and South Africa were analyzed for diversity and for linkage equilibrium by using the Homoplasy Test and compatibility matrices. Horizontal genetic exchange in H. pylori is so frequent that different loci and polymorphisms within each locus are all at linkage equilibrium. These results indicate that H. pylori is panmictic. Comparisons with sequences from Escherichi ...[more]
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Objectives:
To study genetic variations of H. pylori strains based on samples from chronically infected people. To identify the features of strains that might lead to severe stomach problems or stomach cancer.
Eligibility:
People ages 30-70 years who need an upper endoscopy or who were recently diagnosed with stomach cancer
Design:
Participants will be screened by the doctor who does their procedure and a study nurse.
Participants who have endoscopy will have ~6 biopsies removed. These are tissue samples. They are about the size of a grain of rice. Participants will allow the study team to access reports from their stomach exam.
Participants with stomach cancer will donate some of the tissue that will be removed during their clinical care. They will allow the study team to access reports of their surgery. They will also allow them to access the microscope slides of their stomach.
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