title: Fine scale mapping of a genetic locus for conditioned fear.
abstract: Fear conditioning is one of a number of models for investigating the genetic basis of individual variation in emotion and learning. Genetic mapping using crosses between strains of laboratory mice has identified a locus on chromosome one that appears to influence not only variation in conditioned fear, but also in other validated tests of fear-related behaviour, (including the open-field and the elevated-plus maze), suggesting that the rodent locus may act in ways consistent with how a locus influencing susceptibility to anxiety in humans is believed to operate. Here we use high-resolution mapping in genetically heterogeneous mice to show that a quantitative trait locus influencing conditioned fear can be separated from loci influencing open-field activity. Mapping in two different heterogeneous stocks, the Boulder and Northport HS, gave similar map locations for open-field activity at two positions on the current mouse physical map, one at 162 Mb on chromosome one (negative log P-value 5.4) the other at 173 Mb (negative log P-value 4.8), while mapping of contextual conditioned fear in the Boulder HS identified a locus at 170 Mb (negative log P-value 5.4). Estimates of the 95% confidence intervals show that the locations do not overlap. The region containing a gene or genes that influence variation in conditioned fear is approximately 1 megabase in size and contains only one gene of known function, a pre-B cell leukaemia factor.
authors.affiliation: Department of Genetics, University of Leicester, University Road, Leicester LE1 7RH, UK.
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Talbot
authors.forename: Richard A
authors.initials: RA
authors.lastname: Radcliffe
authors.forename: Jan
authors.initials: J
authors.lastname: Fullerton
authors.forename: Robert
authors.initials: R
authors.lastname: Hitzemann
authors.forename: Jeanne M
authors.initials: JM
authors.lastname: Wehner
authors.forename: Jonathan
authors.initials: J
authors.lastname: Flint
mesh_terms: D000818:Animals; D003214:Conditioning, Classical; D005239:Fear; D005838:Genotype; D051379:Mice; D013045:Species Specificity