Review Article | Published:

Dog star rising: the canine genetic system

Nature Reviews Geneticsvolume 5pages900910 (2004) | Download Citation



Purebred dogs are providing invaluable information about morphology, behaviour and complex diseases, both of themselves and humans, by supplying tractable populations in which to map genes that control those processes. The diversification of dog breeds has led to the development of breeds enriched for particular genetic disorders, the mapping and cloning of which have been facilitated by the availability of the canine genome map and sequence. These tools have aided our understanding of canine population genetics, linkage disequilibrium and haplotype sharing in the dog, and have informed ongoing efforts of the need to identify quantitative trait loci that are important in complex traits.

Key Points

  • Dogs were domesticated from the grey wolf and domestication occurred just once and in the Old World.

  • Extensive genome resources for dog genetics include meiotic linkage, cytogenetic and radiation hybrid maps, and a 1.5x poodle sequence and 7.8x boxer sequence.

  • Many breeds of dog derive from few founders and/or have gone through population bottlenecks. As a result, many dog breeds have a highly specific set of inherited disease risks.

  • The top ten diseases in purebred dogs include several that are of concern to human health, such as cancer, epilepsy, autoimmune diseases, blindness, cataracts and heart disease.

  • Genetic clustering methods have been used to define relationships among groups of breeds that often correlate with morphological similarity and geographic origins.

  • Linkage disequilibrium extends from 400 kb to 3 Mb in dog breeds, a nearly ten-fold range in just five breeds assayed, which underlines the importance of choosing the right breed for a whole-genome association study.

  • Extensive linkage disequilibrium indicates that up to 100-fold fewer markers will be needed for whole-genome association mapping in dogs compared with humans.

  • Haplotype diversity in dog breeds is low and sharing of haplotypes is extensive, so sets of haplotype tagging SNPs will probably be useful in many dog breeds.

  • Analysis of canid morphology in the Portuguese water dog demonstrates the value of dog breeds for studies in quantitative genetics.

  • In the near future dog populations might be used to map genes important in behaviour.

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N.B.S. is a Waltham Foundation Fellow. E.A.O. gratefully acknowledges support from the NIH and the Burroughs Wellcome Foundation. We thank Ed Giniger, Kerstin Lindblad-Toh, Ewen Kirkness and Francis Galibert for their thoughtful comments and helpful suggestions on this manuscript, and the AKC and Chet Jezierski for use of the copyrighted canine artwork included in figures 2 and 4.

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  1. National Human Genome Research Institute, National Institutes of Health, 50 South Drive, MSC8002, Building 50, Room 5222, Bethesda, 20892, Maryland, USA

    • Nathan B. Sutter
    •  & Elaine A. Ostrander


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The authors declare no competing financial interests.

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Correspondence to Elaine A. Ostrander.

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An experimentally determined profile of genetic markers that is present on a single chromosome of any given individual.


A taxon or other grouping of organisms consisting of a single species and its descendents.


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A class of repetitive DNA that is made up of repeats that are 2–8 nucleotides in length. They can be highly polymorphic and are frequently used as molecular markers in population genetics studies.


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Bidirectional heterologous chromosome painting using fluorescence in situ hybrization.


A dispersed, intermediately repetitive 300-bp DNA sequence, found in the human genome in 300,000 copies, that is named after the restriction endonuclease (AluI) that cleaves it.


(and supercontig). A contiguous region of DNA sequence constructed by aligning many sequence reads.


A sleep disorder characterized by excessive sleepiness, cataplexy, sleep paralysis, hypnologic hallucinations and an abnormal tendency to pass directly from wakefulness into REM sleep.


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