Color: Silver is a dilution of eumelanin; in addition to body hair being diluted to “silver” or “chocolate”, the mane and tail are usually even lighter. Dapples are also common, where darker pigment outlines lighter colored circles.
Samples Accepted: Blood, Hair
Locus Information: Z series
Test Information: This test is based on a mutation in the SILV (PMEL17) gene. The silver color is incomplete autosomal dominant, and any animal with one copy of the allele will show the affect. A horse with two copies of the allele may be even lighter in color, and may be affected with multiple congenital ocular anomalies (MCOA).
Brunberg, E., Andersson, L., Cothran, G., Sandberg, K., Mikko, S., Lindgren, G. :A missense mutation in PMEL17 is associated with the Silver coat color in the horse. BMC Genetics 7:46, 2006. Doi: 10.1186/1471-2156-7-46.
Andersson, L.S., Wilbe, M., Viluma, A., Cothran, G., Ekesten, B., Ewart, S., Lindgren, G.: Equine Multiple Congenital Ocular Anomalies and Silver Coat Colour Result from the Pleiotropic Effects of Mutant PMEL. PLoS One 8:e75639, 2013. Doi: 10.1371/journal.pone.0075639.
Further information is available at the Online Mendelian Inheritance in Animals website.