The black gene in horses?

Question

I have 3 questions actually. i know that if a horse has the black gene it is expressed, but i have a palomino that has really dark brown/ black spots on her, so i am wondering if the chocolate palomino is a black gene? also, i have a red dun, his parents are a grulla and a palomino, he is red dun but almost all of his tail is black, does he have the black gene? and my last question, i was pretty sure you could only get a bay foal if one of the parents was a bay, because it is the agoti gene, but when we bred our chestnut to a grulla, she had a dark bay, which is odd for that pair,also, the colt has a lot of dun factor, dun factor on his ears, and has stripes all the way up his legs, it is the oddest thing i have ever seen, and i didn't think it was possible for either of those two traits to happen, i know it was possible for the dun factor because grulla is a dun, but i didn't think dun factor was possible on a bay, and i also didn't think bay was possible out of chestnut and grula

Answer 1

palomino is an expression of the creme gene on a red base coat. there is no black gene in a palomino. a red dun would also not have the black gene. he has a base red with the dun factor. if your horse has a black tail he's not a red dun. red duns never have black points. a bay foal has to have at least one parent with an agouti gene, yes you're right. it IS possible to get a bay from that combination because dun is the expression of the dun trait on a bay base coat. are you sure the foal isnt just showing a baby coat? foals are born with a foal coat that can be EXTREMELY different from their adult color. you need to wait until the foal coat sheds off completely (around 3-4 months) to see his true color. bays and duns are very similar in appearance. bays can have dorsal stripes, leg bars, counter shading on the withers, and black tipped ears and still be true bays (i have one), but your colt is probably a dun, just waiting to shed his baby coat. this is a great link for color genetics. each color mentioned also tells you what genes are needed to get that color

http://www.aqha.com/association/download...

*** chocolate palomino is just a SHADE. it's not a genetic color. the horse is a palomino with one red gene and one cream gene no matter what shade it is! ALL palominos are genetically the same. there is no black!

a red dun DOES NOT have black points no matter what color it's parents are. if it has black points it's NOT a red dun. once again, all red duns are genetically the same and they do not carry the black gene

Answer 2

the spots are most likely Bend Or spots.

Answer 3

1.  It can't be a black gene...black and red are the two base colors from which all the others come, with modifiers.  Since black is dominant over red, and the palimino is diluted red, it can't be the black, or it would have expressed.  It must be a modifier, or the horse could be genetically something besides a palimino, like a champagne.  Champagnes have a purple mottling to their skin.  So is it an Amber Champagne instead of a choc pali?

2.  If he's a red dun, he cannot have the black gene, for the same reason above.  It's a base color, not a modifier.

3.  I'm not certain about how the grulla is acheived, whether it looks different shades coming from a red or black base...I mean, there are many different shades of bay, but they are all bays.  Is it the same with grulla?

The first thing that comes to my mind is whether your horses are actually the "color" genetically that they appear to be.  A friend of my sister's was upset to learn she had a champagne instead of a palomino...(Why, I wondered, when it was just for riding and she had the yellow and white she wanted...)

I thought I had a brown tobiano, but she is actually a dilute black.  

For your third, it may be worth the $ to satisfy your curiousity to spend a few bucks and have him tested...because when it comes to color on some of these wacky combinations, "only UC Davis knows for sure"