Stars Sugar N Spice F2-2750, Leopard
Appaloosas that carry the LP gene have three basic characteristics:
Sometimes at birth, some of these may be subdued and develop more with age. Mottled skin is most often seen where there is no hair, or the hair is very thin, such as the muzzle, around the eyes, under the tail, and on the sheath or udder. The eyes have white sclera encircling the iris like a human eye. The hooves have vertical striping as shown in the photos below.
Horses who look phenotypically solid will be registered with an "N" after the F-level (such as F5N-xxxx) unless they show these three characteristics, or test positive for LP. You may need to show clear photos of these three characteristics when registering a horse whose Appaloosa coat pattern is missing or marginal.
See the photos below of the three characteristics. In the next section, you will see the effects of the LP gene in its homozygous form on the color of the hooves.
NOTE: Horses do not have Appaloosa striped hooves on legs with white leg markings. If they have striping, it is the result of ermine marks at the coronet band (see last section).
Chelseas Honey Whirl F2-2743, Mottled Skin and White Sclera
When a horse is homozygous for the LP gene (LP/LP), many times the hooves are a shell color with very light striping, even on horses with black legs, such as in the photos below.
Fewspot Knabstrupper owned by Renee Dubyk
Some horses with white leg markings have ermine marks. If there is any color pigment that touches the coronet band, it can send dark stripes down into the hoof. These are not Appaloosa striped hooves.