Breed Composition

Breeds are populations within an animal species that have been developed through selective breeding. Through targeted selection and mating over many generations, they differ not only in appearance and purpose, but also in the frequency of many genetic variants.

Modern DNA breed analysis makes use of these differences. It does not examine individual ‘breed genes’, but rather many thousands of markers distributed across the genome, known as SNPs. Statistical methods compare an animal’s profile with reference populations. In this way, they determine which breeds individual sections of the genome most closely resemble.

What a breed analysis can achieve depends on the animal species. In dogs, closed studbooks have produced many clearly distinguishable breeds. In horses, by contrast, most breeding populations are linked through cross-breeding. You can find the details on the pages on [breed analysis in dogs] and [breed analysis in horses].

Pet owners can find out where their pet comes from. With mixed-breed animals in particular, appearance often does not allow for reliable conclusions. Even experienced animal shelter staff frequently get this wrong.

Veterinarians receive information about conditions that are more common in certain populations. A breed analysis is not a diagnosis. However, it can provide a reason to investigate specific risks in a targeted manner.

When applied consistently, breeders and breeding organisations can see to what extent populations are purebred, whether there are sub-populations, and how large the proportion of ‘outsider’ blood is. This helps to prevent a further narrowing of the gene pool through targeted mating management.

What matters is not the number of breeds that can supposedly be identified. What is essential is the quality of the genomic data, the reference populations and the statistical method.

A good reference database contains a sufficient number of representative animals for each population. It must also be able to distinguish between closely related populations. If the actual breed of origin is unknown, only the most similar available population can be identified. This is a common cause of unexpected results. Consequently, different providers do not always produce the same findings.

Through decades of work, Generatio has built up one of the largest and most comprehensive reference datasets, which it constantly updates with the latest study data from scientific publications. Our results have been confirmed through multiple cross-checks and show only what can actually be reliably identified.

Please note: A breed analysis determines genetic similarities to reference populations. However, it does not reconstruct specific pedigrees and therefore does not establish breed affiliation under studbook regulations.

SNP data used for breed composition analysis can provide another important piece of population genetic information: to what extent is the genome shaped by common ancestors?

If both parents are descended from common ancestors, the offspring inherit identical DNA segments from both sides. These appear as runs of homozygosity (ROH). Their proportion of the genome determines the genomic inbreeding coefficient GIK_F-ROH. Long ROHs indicate recent common ancestors, whilst shorter ones point to more distant inbreeding events in the ancestors.

Both analyses complement each other perfectly:

1. Where does my animal come from? The breed analysis compares it with reference populations.
2. How closely related were its ancestors? The inbreeding analysis measures homozygous segments in the individual’s genome.