I just gave HERDA and chestnut as examples of genes that don't work like grey. Sometimes it helps to explain how the dominant and recessive genes work differently. HERDA and HYPP are common examples for these inheritance models in the horse world, and I added them in case she was more familiar with those than color genetics. Sorry if that was confusing :o .

Dutchy is correct. In my defense, I wrote it at 3 am... I don't know where anyone is with their genetics background, so I try to give just a "working" explanation if I talk about it online. Some people don't care about the details, and I could keep going for hours.

KG, those generations of color boil down to what genes are in the mare and what she can pass down. The question is whether Grey mare x unknown stallion = non-grey horse if you know that grey normally masks the base horse color. I don't know what's up with the roaned foot, but I think it's cool.

Erin, isn't that basically what I wrote?