U N K N O W N S
There are many things we still do not know about color genetics. This page is dedicated to those things that have yet to be fully researched and isolated. While we do not know much about these things on a genetic level, they still deserve to be seen. These unknowns include mushroom, flaxen, pangare, and sooty.
There are also things that don't fit in any other category on this site. Somatic mutations occur when a gene turns off on random areas of the body. Chimerism happens when one fetus absorbs its twin and takes on its genetic material (does not always manifest physically). Brindle is typically skewed roan or grey, with one genetic exception. Incontinentia Pigmenti is a disease that causes dark pigment along the Lines of Blaschko (vertical lines along the body). The mutation causes skin lesions and is sex-linked, with all horses being female. Male fetuses with the mutation die in utero.
There are also things that don't fit in any other category on this site. Somatic mutations occur when a gene turns off on random areas of the body. Chimerism happens when one fetus absorbs its twin and takes on its genetic material (does not always manifest physically). Brindle is typically skewed roan or grey, with one genetic exception. Incontinentia Pigmenti is a disease that causes dark pigment along the Lines of Blaschko (vertical lines along the body). The mutation causes skin lesions and is sex-linked, with all horses being female. Male fetuses with the mutation die in utero.
A L B I N O ?
Albinism, as is generally defined, has never been documented in horses. The basic definition of albinism is a lack of pigment, which would express as pale pink skin, white hair, and extremely pale blue or pink/red eyes. Aside from congenital mutation, in some other species albinism has been linked to a recessive mutation on what would be the cream/pearl gene in horses. In addition, the way a horse's eye is structured, it cannot possibly appear to be red/pink outside of the typical camera flash "red eye" that happens with most creatures.