International Mammalian Genome Society

17th International Mouse Genome Conference

9-12 November 2003, Braunschweig, Germany

Plenary Presentations * Oral Presentations *
Poster Presentations: Behavioural Genetics and Genomics * Development and Stem Cells * Functional Genome Analysis * Mouse Models of Human Disease * Mouse System Biology Bioinformatics * Multigenic and Multifactorial Trait Analysis * Nutrition and Metabolic Disease * Phenotyping Methods Imaging * The Genetics and Genomics of Infectious Disease *
Verne Chapman Memorial Lecture * Table of Contents * Sponsor/Exhibitor List * Awards * Photographs

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ORAL PRESENTATION

WEDNESDAY 12 NOVEMBER
10:00 – 10:15 HRS

HOST-DEPENDENT VARIATION IN COLONIZATION BY THE GASTROINTESTINAL FLORA

Threadgill D W
University of North Carolina

Co-Authors: Alexander A D, Hench G
Institutions: University of North Carolina

The mammalian gastrointestinal (GI) tract provides a complex ecosystem for numerous bacterial species that in turn modulate susceptibility to disease and infection. Members of the GI flora have been associated with a wide variety of GI homeostatic processes and pathological conditions like colorectal cancer, colitis, antibiotic-associated diarrhea, prevention of opportunistic infections through competitive exclusion, stimulating the immune system, metabolism of toxic compounds and digestion of dietary substances. Since the role played by host genetic variation in influencing colonization dynamics is unknown, we have developed qPCR assays for each member of the Altered Schaedler's Flora (ASF), a standardized bacterial flora that is commonly used to control the host flora during experimental studies. The eight members of this flora contain four extremely oxygen sensitive (EOS), a Bacteroides, a Flexistipes, and two Lactobacilus species. We have re-derived several strains of mice to be germ-free and used these to produce ASF gnotobiotic mice. qPCR assays detected significant differences in ASF colonization between 129 and BALB/c mice showing that host genetics influences gut flora composition. We are currently using these assays to investigate gut flora variation during development of colorectal cancer and gut ecosystem disruption by invading pathogens. Concurrently, we have also developed a modified SAGE assay to monitor the entire endogenous flora during various disease processes and pathological conditions in un-standardized colonies. These assays will be generally applicable to any study investigating the role of GI flora on host biology.