European Genotype Samples
(Neolithic Era/Copper Era)
During the time period between the late Neolithic and Copper Age, black horses emerged in the European population. Over time the population of horses with the Black phenotype increased to the point that there was approximately even numbers of Bay and Black horses.
Five of the ten fossils sampled from this time period contained a genotype coding for the Bay phenotype. These horses all had two dominant Extension Genes (E/E) and at least one copy of the functional Agouti Gene (A/a). Because these fossils had at least one dominant (functional) copy of each of these genes, their base coat color was Bay.
The other five horses sampled from the time period had a genotype that coded for the Black phenotype. All of the fossils that had the coat color genotype for a black horse had two copies of the non-functional Agouti Gene (a/a) with at least one copy of the functional Extension Gene (E).
One of the five horses that had a black phenotype (Pie9) exhibited a mutation at the Extension Locus (e). Because the horse population at the time is assumed to be much larger than the sample taken, it can be assumed that other horses experienced the same mutation resulting in the appearance of the non-functional Extension Allele (e).
None of the horse fossils showed any evidence of having the Overo (EDNRB), Tobiano (KIT13), Sabino (KIT16), Cream (MATP), or either variation of the Silver Gene (SILV9 and SILV11). This shows that the fossils had no variation to their base color.