title: Breed demarcation and potential for breed allocation of horses assessed by microsatellite markers.
abstract: Population demarcation of eight horse breeds was investigated using genotype information of 306 horses from 26 microsatellite loci. The breeds include the indigenous Norwegian breeds Fjord Horse, Nordland/Lyngen Horse, Døle Horse and Coldblooded Trotter together with Icelandic Horse, Shetland Pony, Standardbred and Thoroughbred. Both phylogenetic analysis and a maximum likelihood method were applied to examine the potential for breed allocation of individual animals. The phylogenetic analysis utilizing simple allele sharing statistics revealed clear demarcation among the breeds; 95% of the individuals clustered together with animals of the same breed in the phylogenetic tree. Even breeds with a short history of divergence like Døle Horse and Coldblooded Trotter formed distinct clusters. Implementing the maximum likelihood method allocated 96% of the individuals to their source population, applying an assignment stringency of a log of the odds ratio larger than 2. Lower allocation stringency assigned nearly all the horses. Only three individuals were wrongly allocated a breed by both methods. In conclusion, the study demonstrates clear distinction among horse breeds, and by combining the two assignment methods breed allocation could be determined for more than 99% of the individuals.
authors: Department of Morphology, Genetics and Aquatic Biology, The Norwegian School of Veterinary Science, Oslo, Norway. gro.bjornstad@veths.no
authors: G
authors: G
authors: Bjørnstad
authors: K H
authors: KH
authors: Røed
mesh_terms: D000483:Alleles; D000818:Animals; D001947:Breeding; D005787:Gene Frequency; D014644:Genetic Variation; D006736:Horses / Q000145:classification* / Q000235:genetics*; D007055:Iceland; D016013:Likelihood Functions; D008126:Lod Score; D018895:Microsatellite Repeats / Q000235:genetics*; D009664:Norway; D010802:Phylogeny; D013045:Species Specificity