HGG Community Forums

I'd like to clarify the post above a bit, if I may. First, understand that all of these unfortunate occurrences are based on what happens in real life. This is not something simply invented for the game to make it difficult.

Breeding a frame carrying horse to another frame carrying horse gives a 1 in 4 chance of producing a foal that is homozygous for frame. This causes an incomplete digestive system which results in the foal dying from impaction colic within a few days of its birth. (In the game it is reported as a dead foal immediately.) This is why the frame gene is written as Olw, for Overo, lethal white. Frame does not show up much unless a horse has one of the white producing genes--splash, Kit whites, Kit sabinos, and Kit tobiano. So, if you haven't color tested a horse, it might be carrying Frame and you won't know it unless you breed it to another horse with frame and get that dead foal. If you test a horse and find that it has frame, you might also see that it has a larger White Factor than is visible--the Frame does tend to suppress all white markings, but it is most noticeable when crossed with the Dominant White mutations and homozygous Splash 1, where it produces that "framing" placement of pigment that is typical of the "Overo" pattern of paints and pintos.

The four Dominant White mutations of the Kit gene break that gene badly enough that when a foal inherits one of them from each parent, it dies in utero, before birth. So breeding a horse with any of the dominant whites with another with dominant white has a 1 in 4 chance of producing a dead foal. You can't breed for a horse with both White 2 and White 4, for instance.

You can safely breed two horses with the same sabino variety or any of the three sabinos together. However, crossing Sabino 1 or Sabino 2 with White 1 or White 2 can produce a dead foal. Sabino 1 and 2 CAN be safely crossed with White 3 and White 4.

You can safely breed two horses with Splash 1 together, and you can safely breed Splash 1 with either Splash 2 or Splash 3. However, Splash 2 and Splash 3 are homozygous lethal and those two versions of splash are lethal when combined.

In all cases there is a 1 in 4 chance of the foal inheriting the dangerous gene from both parents and dying.

Tobiano and Roan, the other Kit mutations, can be safely bred with themselves, all other Kit mutations, the three Splash mutations, and Frame.