Fox domestication: Molecular mechanisms involved in selection for behavior

Abstract

Although animal domestication has enjoyed the attention of geneticists and evolutionary biologists since Darwin’s times, the focal question about the genetic basis of this process has not been duly considered. We present some results of experimental modeling of historical domestication in silver foxes (Vulpes vulpes), an object of commercial breeding. Attention is focused on the role of artificial selection in the transformation of the behavior of these animals, which has brought about unique populations of tame and aggressive foxes. Additional resources were developed to analyze the molecular nature of differences in the behavior of these unique foxes: the meiotic map of the fox genome was constructed, informative segregating subpopulations were obtained by crosses of tame and aggressive animals, and the formerly applied method of behavioral phenotype quantification was improved. The integrated behavioral phenotypes (principal components PC1 and PC2) used in the study were obtained by analysis of ethological parameters recorded with a camcorder. The most important result is that the region most closely associated with tame behavior was identified on fox chromosome 12 by QTL interval mapping. The principle significance of this result is strengthened by the fact that the region is similar to the region on dog chromosome 5, presumed to be responsible for the early domestication of wolves and their evolutionary transformation to primitive dogs.