Pearl Horses

What is Pearl?
Pearl is a newly discovered Dilution gene in horses. The color name "pearl" was selected in ~2003 by the group of owners and breeders of Iberian-bred American pearl horses in the newdilutions Yahoo Group.

The Pearl gene is a RECESSIVE, cream-activated, dilution gene.

*Recessive means that one copy of the gene in a horse has no expression (is "invisible"), and two copies (homozygosity) results in full expression (dilutes the base color once).

*Cream-activated means that it also reacts with cream: it shows up, adding another instance of dilution, if there is a cream gene present. In this case it manifests as a "double dilution": pearl AND cream.

Pearl basically works making a single cream gened horse to look like it has a double cream dilution.

How It was Found:
There had been noticed, and documented, several startling cases of a cream dilute horse being crossed with a base color horse (chestnut, bay, black, brown) and producing a foal that looks like a double cream dilute, in two Andalusian "families" in the USA, as detailed below.

When these foals were color tested, without exception they were found to have only one cream gene, as expected by their parentage. (This parentage is almost always DNA verified because of the regulations of the Iberian breeds involved.)

Now, most of these foals have also been tested for Pearl, and those who have been tested all carry it.

The cream dilutes never produced these colors except when bred to the same particular dark-colored horses. That's how it was first noticed.