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Table 5.

Primary Color Z Bay Silver Bay Black Silver Black or Silver Dapple Seal Brown Silver Brown Chestnut Chestnut Buckskin Silver Buckskin Smoky Black Silver Smoky Black Palomino Palomino Bay Dun Silver Dun Grullo Silver Grullo

The hypothesis that silver dapple horses are homozygotes, and silver black horses are heterozygous for this mutation could not be confirmed by DNA tests.

Some silver horses have congenital anomalies of the structure of eyes called anterior segment dysgenesis (ASD). Scientific literature also uses the name multiple congenital ocular abnormalities (MCOA). The phenotypes include:

 Small pupils, which do not react to light or react poorly. (Application of dilating preparations does not have an effect.)

 Abnormally formed pupils.

 Hypoplasia (underdevelopment) of the iris, including its stroma.

 Hypoplasia of iris formed by a pigmentary layer on the top edge of the pupil.

 Abnormal structure of pectineal ligament.

 Cataracts.

 Cysts in the vitreous body.

 Corneal thickening.