Is CSNB in the Appaloosa connected to a particular coat pattern?
Yes – Our research has shown that CSNB is associated with Appaloosa coat patterning of a specific type. Appaloosas with coat patterns that indicate they are homozygous for LP are affected (diagram above). Appaloosas with spotted coat patterns are heterozygous for LP, and are not affected by CSNB (diagram below). Also, horses that are true solid non-characteristic Appaloosas, with no dominant copies of LP, are not affected by CSNB. It is important to note that some Appaloosas are born with little or no white patterning. These horses may or may not be homozygous for LP. One cannot determine what their probable genotype is by coat pattern alone. These horses would have to be tested for CSNB and/or LP in order to identify them correctly. Currently a DNA test is not available.
