title: Behavioral responses to novelty and structural variation of the hippocampus in mice. II. Multivariate genetic analysis.
abstract: On the basis of results from lesion studies in rodents, covariations are expected to exist between naturally-occurring heritable variations in hippocampal morphology and exploratory behavior elicited by novel surroundings. For this reason, we set up a full diallel cross between five inbred mouse strains and analyzed the behavioral and the hippocampal anatomical variation in male animals from this cross. Employing a bivariate extension of the diallel-cross analysis, estimates were obtained for the phenotypical, environmental, and genetical correlations between the phenotypes studied. A factor analysis performed on the matrix of additive-genetic correlations revealed that variations in the size of the intra- and infrapyramidal mossy fiber terminal fields (iip-MF) are negatively related to open-field exploration and novelty-induced fear. These results indicate that having larger iip-MF projections promotes the collection and processing of information about a novel environment, entailing lower levels of exploration and fear.
authors.affiliation: Institut für Humangenetik und Anthropologie, Universität Heidelberg, F.R.G.
authors.forename: W E
authors.initials: WE
authors.lastname: Crusio
authors.forename: H
authors.initials: H
authors.lastname: Schwegler
authors.forename: J H
authors.initials: JH
authors.lastname: van Abeelen
mesh_terms: D000818:Animals; D001143:Arousal / Q000502:physiology*; D001931:Brain Mapping; D003433:Crosses, Genetic; D005106:Exploratory Behavior / Q000502:physiology*; D006624:Hippocampus / Q000502:physiology*; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains / Q000235:genetics*; D009043:Motor Activity / Q000502:physiology; D009412:Nerve Fibers / Q000502:physiology; D010641:Phenotype; D013045:Species Specificity