Frame Overo creates markings on the horse’s face but no large markings on their legs. Frame Overo horses are often seen with blue eyes due to the extensive face markings. The white on Frame Overos starts on the sides of the horse on the barrel, neck and rump and stretch outwards. Rarely the white touches the top line of the horse (though when this happens it is often on the neck). On Frame Overos where the coloured areas meet the white areas are often rigid. Frame Overo’s tails are always solid colour. The more minimal Frame Overos may just have bold face markings and possibly a small mark on it’s side where as the extensive horses will have white sides, loud face markings but still solid coloured tails and legs.

Homozygous Lethal

Frame Overo horses are homozygous lethal. Unlike most homozygous lethal combinations where the fault results in aborted pregnancy, homozygous Frame Overo horses are born but die in a few days. This is called Overo Lethal White Syndrome. As the name suggests the foals are born completely, or nearly, white with blue eyes. The foal’s digestive system isn’t formed normally so the foal dies a tragic death if not put down quickly.
Tawny Horse does not support the breeding of Frame to Frame horses, Frame to Frame breeders say 25% chance of a lethal foal isn’t that high, we at Tawny Horse say a 25% chance of a lethal foal is way too high. Have your horse tested for Frame and if tested positive, do not be an irresponsible breeder by breeding Frame to Frame horses. 

Frame Overo Genetics

Frame Overo is a dominant gene and genetic testing is available to the public. The Frame Overo mutation is found at the EDNRB locus. Some people prefer to write it as Fr in a genome, standing for Frame, but I prefer Ov standing for Overo.

Check out pictures of Frame Overo horses in the Frame Overo albums: