Stability of inbred mouse strains in behavior and brain size between laboratories and across decades

Department of Psychology, University of Alberta, Edmonton, AB, Canada T6G 2E9.
Proceedings of the National Academy of Sciences (Impact Factor: 9.67). 11/2006; 103(44):16364-9. DOI: 10.1073/pnas.0605342103
Source: PubMed


If we conduct the same experiment in two laboratories or repeat a classical study many years later, will we obtain the same results? Recent research with mice in neural and behavioral genetics yielded different results in different laboratories for certain phenotypes, and these findings suggested to some researchers that behavior may be too unstable for fine-scale genetic analysis. Here we expand the range of data on this question to additional laboratories and phenotypes, and, for the first time in this field, we formally compare recent data with experiments conducted 30-50 years ago. For ethanol preference and locomotor activity, strain differences have been highly stable over a period of 40-50 years, and most strain correlations are in the range of r = 0.85-0.98, as high as or higher than for brain weight. For anxiety-related behavior on the elevated plus maze, on the other hand, strain means often differ dramatically across laboratories or even when the same laboratory is moved to another site within a university. When a wide range of phenotypes is considered, no inbred strain appears to be exceptionally stable or labile across laboratories in any general sense, and there is no tendency to observe higher correlations among studies done more recently. Phenotypic drift over decades for most of the behaviors examined appears to be minimal.

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Available from: Alexander A Bachmanov, Nov 25, 2014
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    • "under study (Sena et al., 2010). Although less well studied, there is no reason to assume that issues regarding quality of research are different in psychopharmacology than in other fields of CNS research (Wahlsten et al., 2006; Button et al., 2013; Groenink et al., 2014). "
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    • "However, these issues have been poorly explored so far and hence require a more thorough investigation (Tian et al., 2009). Genetically distinct inbred mice differ from one another in their anxiety traits and other behaviors concerning their locomotor activities, stress responses, learning skills, and drug responses (Hovatta and Barlow, 2008; Wahlsten et al., 2006). Here, we took advantage of these well-characterized inbred mice strains, and utilized a series of approaches, including flow cytometry, RT-qPCR, genome-wide brain transcriptome analysis, genotype–phenotype correlation, and gene functional clustering, to examine the profile of microglial activation, and to explore its association with anxiety-related behaviors among these strains. "
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    • "Except for elevated plus maze where no ethanol was administered, the ethanol effect was analyzed as a repeated measure for pre-versus post-injection. The table shows that strain differences on all measures were clearly significant, a finding that was expected because the strains were chosen on the basis of large differences on the same tests in previous studies [13] [35]. Most measures also showed a large ethanol effect, as expected from previous studies. "
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