Variation in Gut Microbiota Strongly Influences Individual Rodent Phenotypes

Open Access
Publisher Website
Google Scholar
Abstract
Understanding genetic and phenotypic differences between experimental animals (both within a single population and between populations held at different sites) is potentially important in explaining variability in responses to drugs and other stressors. Population changes in endogenous and exogenous metabolism in laboratory animal colonies have often been ascribed to genetic drift in the experimental animals themselves. This undoubtedly occurs in laboratory rodents; however, phenotypic drift in animal colonies can have an immediate and potentially greater short term impact on normal physiological variation and mammalian metabolism, as exemplified by Robosky et al. in this issue of Toxicological Sciences. They describe clear and stable metabolic differentiation of two groups of rats of identical strain obtained from the same supplier, but housed in separate rooms within the supplier's barrier unit. These observations were based on urinary metabolite signatures defined by 1H NMR spectroscopy and mass spectrometry (MS), which comprise thousands of low-molecular-weight molecules in a range of concentrations that can be profiled and interpreted using computer-based pattern recognition methods.