Color 101: Base colors & the Agouti/Brown modifier

BASE COLOR
All horses base coat color is either black or red.

On a color test ...
Black is represented on a color test as 'E' and is dominant.
Red is represented as 'e' and is recessive.

So a black horse could be - EE (homozygous) or Ee (heterozygous)
A red horse will always be - ee (homozygous)

MODIFIERS

The Agouti gene is some times call the bay gene. This gene restricts black pigment to the points of a horse - mane, tail, legs. It is represented as 'A' or 'At' (brown). Agouti doesn't show itself on a red horse. A horse with NO agouti will be represented by a lower case 'a'.

Below are possibly color test results for black, bay, brown and red.

BLACK: EE aa or Ee aa (no agouti)
BAY: EE Aa, EE AA, Ee Aa, EeAA
BROWN: EE Ata, EE AtAt, Ee Ata, Ee AtAt
RED: ee aa, ee Aa, ee AA, ee Ata, ee AtAt

Think of it as a formula with the horse getting one base color from each parent resulting in either a homozygous or heterozygous black or red horse. Once you know that you just add one or two modifiers to the base color altering its appearance.

THANK YOU!!!

That helps much! I'm copying that info as I was confused as to how to get Red and Brown. I also, kept getting told that there was no such thing as brown, but I grew up with several horses that I believe would have qualified genetically as brown and have since produced 5 ponies (full sisters) out of the black combination parents. I swear they were brown - yet kept having people say that brown wasn't possible from two black parents.

Would love to cross some of those mares back on my Silver stallion - to see what we'd get - but I'd sold all of them before getting the silver boy.

You're Welcome!

I am hoping to get the website and this forum more updated in the next month or two. I am still fairly new to hosting a forum but I will also look into horse smilies

Brown is most definitely out there. Pet DNA Services of AZ has been developing a test for it. My boy Champs Guthrie was tested by them a couple years ago. He came back 'At' one copy of the brown gene. I know his daughter, Amelia and his son, Draco both must be browns as well.

Also a couple days ago I was contacted by the freelance writer for APHA. She was the one who did the silver article last February in the Paint Horse Journal. They will be doing and article in the next couple months on brown. Guthrie will be an example I guess. So brown like silver is slowing being understood and acknowledged by more and more horse owners.

Awww, Guthrie's going to be the "star" of an article? That's neat!

So how do you go out and find the smileys? I can send you towards another forum to look at some of their smileys, but have no idea where or how they got them. Could find out I guess...

Storm has started early here, temp is back down to freezing and I'll soon be bringing the little mare in. This might be when she foals... I'd forgotten what it was like to wait on pins and needles for a mare to drop the foal - even when dates known. The last two were larger foals and the mares hadn't given any real indications of being "ready" but they sure weren't happy about being stalled and both foaled outside before being brought in for the night - but the weather was mild - both in April and October...

Can't wait to see what your fella sires out of the pony mare. In case you can't tell, I like the ponies! She's gorgeous.