genetic color question

Ok so I was learning about my mares dam. I was told she was homozygous for black (she's a black and white tobiano APHA) they said she can't throw red foals? Is that true? What if she were bred to a chestnut colored stallion? Would the foal still be black and white?
This is just for curiousity sake ...
Posted via Mobile Device

Yes. Being homozygous black, she will NEVER be able to produce a red based foal. Chestnut/Sorrel, Palomino, Red Dun, Cremello etc. Anything that is e/e. Your mare will only be able to produce E/e foals (or E/E depending on what she's bred to) So her resulting foal will always be black based like black, bay, grulla, perlino, buckskin, etc.

Ok thanks that's extremly helpful... so is this how buckskin paints happen? Like breeding the mother with a buckskin stud?
Posted via Mobile Device

^^^ that depends on the buckskin stud and his color and agouti genes. If he is homozygous agouti, you would still only have about a 50% chance at a buckskin foal since he would only have one dilution gene.

The only way to guarantee a buckskin foal when the dam is a homozygous black tobiano is if the sire is a cremello (double dilute) and homozygous agouti.
Posted via Mobile Device

Ok one more question... can a palomino mare produce a grullo foal? We have a mare we are not 100% on her color. All we know is her dam was palomino. Some people have called her a buckskin, some a dun, and some a grullo. I personally think sooty buckskin but I don't know enough about genetics to say forsure. I'll try uploading a picture soon
Posted via Mobile Device

Sure can. Depends on what the stud was.

This is the mare. I have no clue what color the stud was
Posted via Mobile Device

With some horses, the only way to know for sure is to do genetic testing LOL

But the question shouldn't be just what a palomino can produce, (which they are one dilute gene over a red coat) but what does the sire of the foal have to contribute?
Posted via Mobile Device

Right! Mostly I was curious what color everyone thinks this girl is. I asked the question the way I did because I was under the inpression that a palomino could never proclduce a grullo ..not sure why. Like I said I don't know much about genetics. Im glad I don't breed horses... its too confusing! LOL
Posted via Mobile Device

She looks like a sooty buckskin to me, but I am not a color genius by any means.