title: Confirmation and genetic dissection of a major quantitative trait locus for alcohol preference drinking.
abstract: OBJECTIVE
  In previous work, we created congenic strains that carry the DBA/2IBG (D2) region for alcohol preference on chromosome 2, on an otherwise C57BL/6IBG (B6) background. Here, we report construction and testing of interval-specific congenic recombinant strains (ISCRSs) for the purpose of narrowing the quantitative trait loci (QTL) interval.
  
  
  METHODS
  ISCRSs were derived by identifying mice that carry recombination events in the D2 interval, during the backcrossing for congenics. Recombinant mice were backcrossed to B6, and progeny that carry the reduced chromosome 2 region were tested for its effect on the alcohol preference phenotype.
  
  
  RESULTS
  We developed multiple ISCR strains, which spanned the QTL interval. Three of these showed the D2 phenotype of reduced alcohol consumption. The overlap of two of these strains reduced the QTL interval from 66.8 to 3.5 Mb. A third positive ISCRS suggests the possibility of a second, linked QTL.
  
  
  CONCLUSIONS
  Use of ISCRSs can narrow a QTL region to a few Mb. This reduced interval size will facilitate identification of candidate genes, through bioinformatics, gene expression, and DNA sequencing strategies. Potential difficulties, including reduced power as a result of variable phenotypes or small effect size, are discussed.
authors.affiliation: Institute for Behavioral Genetics, CB 447, University of Colorado, Boulder, CO 80309-0447, USA.
authors.forename: Cathy
authors.initials: C
authors.lastname: Ruf
authors.forename: Phyllis
authors.initials: P
authors.lastname: Carosone-Link
authors.forename: Justin
authors.initials: J
authors.lastname: Springett
authors.forename: Beth
authors.initials: B
authors.lastname: Bennett
mesh_terms: D000428:Alcohol Drinking / Q000235:genetics*; D000818:Animals; D005260:Female; D008297:Male; D051379:Mice; D020297:Mice, Congenic; D040641:Quantitative Trait Loci / Q000235:genetics*; D013045:Species Specificity