Rapid selection response for contextual fear conditioning in a cross between C57BL/6J and A/J (palme-affy-mouse-198967)

These data are from the brains (amygdala and hippocampus) of mice originally derived from a cross between C57BL/6J and A/J inbred strains. We used short-term selection to produce outbred mouse lines with differences in contextual fear conditioning, which is a measure of fear learning. We selected for a total of 4 generations. Fear learning differed in the selected lines and this difference was stronger with each successive generation of selection. We identified several QTLs for the selection response, including a highly significant QTL at the tyr locus (p < 9.6(-10)). We used Affymetrix microarrays to identify many differentially expressed genes in the amygdala and hippocampus of mice from the final generation of selection. Amygdala and hippocampus samples were rapidly dissected out of experimentally nave mice from each selected line. Three samples were pooled and hybridized to each array. Experimentally nave mice were used because the behavior of the mice can be reliably a nticipated due to their lineage. Thus these gene expression differences are not due to the response to human handling, foot shock or fear-inducing conditioned stimuli. We have a second similar study that focuses on a different selected population that was based on C57BL/6J and DBA/2J mice (see GES4035).

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