Alcohol Clin Exp Res 1999 Jul;23(7):1262-71
Alcohol Research Center, Institute for Behavioral Genetics, University of
Colorado, Boulder 80309-0447, USA. Valerie.Whatley@colorado.edu
BACKGROUND: C57BL/6 inbred mice prefer alcohol whereas DBA/2 mice avoid it. We describe the construction of congenic strains of mice in which DBA/2 alleles for alcohol avoidance were placed on a C57BL/6 background using phenotypic selection. METHODS: Mice were primed to drink 10% v/v ethanol in water for 2 days before a two-bottle choice paradigm. N2 males who demonstrated an alcohol-avoidance phenotype were backcrossed to B6 females to construct 15 independent lines. RESULTS: Eight of these lines were lost due to failure to breed or absence of males with an alcohol-avoidance phenotype. The remaining sublines were split to form a total of 21 sublines. In the N7 and N9 generations, a genome scan located provisional quantitative trait loci (QTLs) on chromosomes 1, 2, 3, 6, and 9. Progeny testing confirmed QTLs on chromosomes 1 and 2. CONCLUSIONS: The QTL on chromosome 2 overlaps the 95% confidence interval of Alcp1 whereas that on chromosome 1 is new and has been calledAlcp5. Marker-assisted selection was used in the N9 and subsequent generations to maintain the congenic lines and produce congenic strains.