With the sequencing of the complete genome of several domestic animal species including the bovine, several high-throughput technologies are now available to genotype several tens of thousands SNP markers simultaneously spanning the entire genome.

Although these markers do not have any biological effect, some of them may be located close to the genes responsible for the genetic variability and, therefore, may predict their effect. This property is applied in genomic selection.

Marker effects are estimated in a reference population with both phenotypes and genotypes. These effects are then used to predict the breeding value of an individual characterized by marker information only, possibly at birth.