Origin, genetic diversity, and genome structure of the domestic dog

Abstract

Comparative analysis of mammalian genomes provides important insight into the structure and function of genes. However, the comparative analysis of gene sequences from individuals of the same and different species also provides insight into the evolution of genes, populations, and species. We exemplify these two uses of genomic information. First, we document the evolutionary relationships of the domestic dog to other carnivores by using a variety of DNA‐based information. A phylogenetic comparison of mitochondrial DNA sequences in dogs and gray wolves shows that dogs may have originated from multiple wolf populations at a time much earlier than suggested by the archaeologic record. We discuss previous theories about dog development and evolution in light of the new genetic data. Second, we review recent progress in dog genetic mapping due to the development of hypervariable markers and specific chromosome paints. Extensive genetic homology in gene order and function between humans and dogs has been discovered. The dog promises to be a valuable model for identifying genes that control morphologic differences between mammals as well as understanding genetically based disease. BioEssays 21:247–257, 1999. © 1999 John Wiley & Sons, Inc.

Sequence Comparison of the Dopamine Receptor D4 Exon III Repetitive Region in Several Species of the Order Carnivora.

“…Based on the DNA-DNA hybridization test, it has been suggested that the family Canidae might have diverged at an earlier time than other carnivore families, approximately 50 million years ago [17]. The present data imply that the repetitive region of DRD4 gene might have developed following the divergence of the family Canidae.…”

Breed-typical behaviour in dogs—Historical remnants or recent constructs?

“…The domestication of the dog has resulted in considerable variety in morphology, genetics and behaviour (e.g. Scott and Fuller, 1965;Wayne, 1986;Wayne and Ostrender, 1999). The first evidence of distinct dog types is dated back to 3000-4000 year BP (Harcourt, 1974), and since then there has been increased variation and specialization.…”

Unleashing the Canine Genome

“…Gene flow between breeds is restricted by the pedigree barrierregistering a dog as a member of a particular breed requires that both of the dog's parents be registered members of that same breed. Most modern dog breeds are relatively young, with the majority having been developed within the last 300 yr (Wilcox and Walkowicz 1995;Wayne and Ostrander 1999). Many of these were derived from a small number of founders-as few as six in the case of the modern Irish Wolfhoundthat best represented the physical or behavioral traits breeders wished to feature in a given breed.…”