Unknown Mysteries of Equine Genetics - Silver (Z) and Cream (Cr)

Think we're very far along in knowing all about horse genetics? Nay (or neigh?), we actually aren't. There is so much more to know about genetics and how they function that even after a lifetime of studying, I doubt one would know everything. God definitely has made the equine - along with all other animals - a complex, gorgeous structure of living, feeling, mass. They even can have personalities!

This time I'll be writing some more about the Silver (Z) gene, and a theory pertaining to it and the Cream (Cr) gene. I'm apt to call it simply a hypothesis, but genetic testing would say otherwise. So, it is a theory.

The theory is that the Cream (Cr) gene can carry and inhibit the phenotype of the Silver (Z) gene.

Where did I hear of this? It actually wasn't in Sponenberg's latest book on equine genetics, so it must be a pretty recent thing; or, perhaps, just rarely heard of. Either way, I was browsing through a horse forum and saw this gorgeous buckskin in an icon off to the side. Of course, being me, I had just had to click on this stud's picture:

Taking advantage of the link to the lucky breeding stable that owns this stud, I read some about him and learned that he throws Silver foals! In case you want to read some more about him, or want to view images of him, I'll link you to Willow Bend Farm's page about Golden.

Now get this: Proven from scientific studies, the Silver gene will *always* dilute black on a horse that is Z-positive. Which, as you can tell, creates a problem, as Gold has very, very black points.

Something that I found interesting, though, was that up until he was about three or four years of age, his mane had silver in it. And as a six-week old foal, he appeared to be a chestnut! I'm not sure if this is normal or not for buckskins, but if you're curious- just check out that link. :)

If this hypothesis is proven, we shall know a bit more about horse genetics. However, Silver will still show on most Cream-based dilutes. Here are two silver buckskins for ya.

And, that'll be all folks! I'd love to receive some feedback on this, whether it be comments, suggestions for blog posts, or questions, so think it over. :)